Pulley Lesson PowerPoint, Simple Machines

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A three part 1500+ PowerPoint slideshow from www.sciencepowerpoint.com becomes the roadmap for an interactive and amazing science experience that includes a bundled homework package, answer keys, unit notes, video links, review games, built-in quizzes and hands-on activities, worksheets, rubrics, games, and much more.
Also included are instruction to create a student version of the unit that is much like the teachers but missing the answer keys, quizzes, PowerPoint review games, hidden box challenges, owl, and surprises meant for the classroom. This is a great resource to distribute to your students and support professionals.
Text for the unit PowerPoint is presented in large print (32 font) and is placed at the top of each slide so it can seen and read from all angles of a classroom. A shade technique, as well as color coded text helps to increase student focus and allows teacher to control the pace of the lesson. Also included is a 12 page assessment / bundled homework that chronologically follows the slideshow for nightly homework and the end of the unit assessment, as well as a 8 page modified assessment. 9 pages of class notes with images are also included for students who require assistance, as well as answer keys to both of the assessments for support professionals, teachers, and homeschool parents. Many video links are provided and a slide within the slideshow cues teacher / parent when the videos are most relevant to play. Video shorts usually range from 2-7 minutes and are included in organized folders. Two PowerPoint Review games are included. Answers to the PowerPoint Review Games are provided in PowerPoint form so students can self-assess. Lastly, several class games such as guess the hidden picture beneath the boxes, and the find the hidden owl somewhere within the slideshow are provided. Difficulty rating of 8 (Ten is most difficult).
Areas of Focus: -Newton's First Law, Inertia, Friction, Four Types of Friction, Negatives and Positives of Friction, Newton's Third Law, Newton's Second Law, Potential Energy, Kinetic Energy, Mechanical Energy, Forms of Potential to Kinetic Energy, Speed, Velocity, Acceleration, Deceleration, Momentum, Work, Machines (Joules), Catapults, Trajectory, Force, Simple Machines, Pulley / (MA Mechanical Advantage), Lever /(MA),Wedge /(MA), Wheel and Axle (MA), Inclined Plane / (MA), Screw /(MA).
This unit aligns with the Next Generation Science Standards and with Common Core Standards for ELA and Literacy for Science and Technical Subjects. See preview for more information
If you have any questions please feel free to contact me. Thanks again and best wishes. Sincerely, Ryan Murphy M.Ed www.sciencepowerpoint@gmail.com
Teaching Duration = 4+ Weeks

Published in: Education, Business, Technology

Pulley Lesson PowerPoint, Simple Machines

  1. 1. 40 N 20 N FO FI 20N 40N = 2 MA
  2. 2. • RED SLIDE: These are notes that are very important and should be recorded in your science journal. Copyright © 2010 Ryan P. Murphy
  3. 3. -Nice neat notes that are legible and use indentations when appropriate. -Example of indent. -Skip a line between topics -Make visuals clear and well drawn. Please label. Effort Arm Resistance Arm
  4. 4. • RED SLIDE: These are notes that are very important and should be recorded in your science journal. • BLACK SLIDE: Pay attention, follow directions, complete projects as described and answer required questions neatly. Copyright © 2010 Ryan P. Murphy
  5. 5. • http://sciencepowerpoint.com/
  6. 6.  Mechanical advantage (MA): The number of times a machine multiplies your effort force. Copyright © 2010 Ryan P. Murphy
  7. 7.  To find MA  Divide resistance force (usually weight in g) by the effort force (Newtons) Copyright © 2010 Ryan P. Murphy
  8. 8.  To find MA  Divide resistance force (usually weight in g) by the effort force (Newton) Copyright © 2010 Ryan P. Murphy
  9. 9.  To find MA  Divide resistance force (usually weight in g) by the effort force (Newton) Copyright © 2010 Ryan P. Murphy
  10. 10.  To find MA  Divide resistance force (usually weight in g) by the effort force (Newton) Copyright © 2010 Ryan P. Murphy
  11. 11.  To find MA  Divide resistance force (usually weight in g) by the effort force (Newton) Copyright © 2010 Ryan P. Murphy
  12. 12.  To find MA  Divide resistance force (usually weight in g) by the effort force (Newton) Copyright © 2010 Ryan P. Murphy FO = MA
  13. 13.  To find MA  Divide resistance force (usually weight in g) by the effort force (Newton) Copyright © 2010 Ryan P. Murphy FO FI = MA
  14. 14. • Find the MA of the following. • The work input was 2, and the output was 18.
  15. 15. • Find the MA of the following. • The work input was 2, and the output was 18.
  16. 16. • Find the MA of the following. • The work input was 2, and the output was 18. FI FO
  17. 17. • Find the MA of the following. • The work input was 2, and the output was 18. FI FO
  18. 18. • Find the MA of the following. • The work input was 2, and the output was 18. FI FO
  19. 19. • Find the MA of the following. • The work input was 2, and the output was 18. FI FO 2 18
  20. 20. • Find the MA of the following. • The work input was 2, and the output was 18. FI FO 2 18 = 9 MA
  21. 21. • Find the MA of the following. • The work input was 2, and the output was 18. FI FO 2 18 = 9 MA Mechanical Advantage: Learn More at… http://www.wisc- online.com/objects/ViewObject.aspx?ID=ENG20504
  22. 22. 12 N 6 N
  23. 23. 12 N 6 NFO FI
  24. 24. 12 N 6 NFO FI
  25. 25. 12 N 6 NFO FI
  26. 26. 12 N 6 NFO FI 6N 12N
  27. 27. 12 N 6 NFO FI 6N 12N = 12 MA
  28. 28. 40 N 20 N
  29. 29. 40 N 20 N FO FI
  30. 30. 40 N 20 N FO FI
  31. 31. 40 N 20 N FO FI 20N 40N
  32. 32. 40 N 20 N FO FI 20N 40N = 2 MA
  33. 33. 40 N 20 N FO FI 20N 40N = 2 MA
  34. 34. 90 N 45 N
  35. 35. 90 N 45 N FO FI
  36. 36. 90 N 45 N FO FI 45N 90N
  37. 37. 90 N 45 N FO FI 45N 90N = 2 MA
  38. 38. • Law Conservation of Energy
  39. 39. • Law Conservation of Energy – Energy cannot be created or destroyed.
  40. 40. • Law Conservation of Energy – Energy cannot be created or destroyed. – Energy can be transferred.
  41. 41. • Law Conservation of Energy – Energy cannot be created or destroyed. – Energy can be transferred.
  42. 42. • Law Conservation of Energy – Energy cannot be created or destroyed. – Energy can be transferred.
  43. 43. • Video Links! Mechanical Advantage, Khan Academy, Optional (Advanced) (I,II,III) – http://www.khanacademy.org/science/physics/m echanics/v/introduction-to-mechanical-advantage (Part 1) – http://www.khanacademy.org/science/physics/m echanics/v/mechanical-advantage--part-2 (2) – http://www.khanacademy.org/science/physics/m echanics/v/mechanical-advantage--part-3 (3)
  44. 44.  Simple machines: Types of machines that do work with one movement. Copyright © 2010 Ryan P. Murphy
  45. 45.  Simple machines: Types of machines that do work with one movement. Copyright © 2010 Ryan P. Murphy
  46. 46.  Simple machines: Types of machines that do work with one movement. Copyright © 2010 Ryan P. Murphy
  47. 47.  Simple machines: Types of machines that do work with one movement. Copyright © 2010 Ryan P. Murphy
  48. 48.  Simple machines: Types of machines that do work with one movement. Copyright © 2010 Ryan P. Murphy
  49. 49.  Simple machines: Types of machines that do work with one movement. Copyright © 2010 Ryan P. Murphy
  50. 50.  Simple machines: Types of machines that do work with one movement. Copyright © 2010 Ryan P. Murphy
  51. 51.  Simple machines: Types of machines that do work with one movement. Copyright © 2010 Ryan P. Murphy
  52. 52.  Simple machines: Types of machines that do work with one movement. Copyright © 2010 Ryan P. Murphy
  53. 53.  Simple machines: Types of machines that do work with one movement. Copyright © 2010 Ryan P. Murphy
  54. 54. • Simple Machines Available Sheet: Pulleys
  55. 55.  Pulley  Uses grooved wheels and a rope to raise, lower or move a load. Copyright © 2010 Ryan P. Murphy
  56. 56.  Pulley  Uses grooved wheels and a rope to raise, lower or move a load. Copyright © 2010 Ryan P. Murphy
  57. 57.  A pulley makes work seem easier Copyright © 2010 Ryan P. Murphy
  58. 58.  A pulley makes work seem easier Copyright © 2010 Ryan P. Murphy
  59. 59.  A pulley makes work seem easier  Changes the direction of motion to work with gravity. Copyright © 2010 Ryan P. Murphy
  60. 60.  A pulley makes work seem easier  Changes the direction of motion to work with gravity. Instead of lifting up, you can pull down. Copyright © 2010 Ryan P. Murphy
  61. 61.  A pulley makes work seem easier  Changes the direction of motion to work with gravity. Instead of lifting up, you can pull down.  Uses your body weight against the resistance. Copyright © 2010 Ryan P. Murphy
  62. 62.  The more pulleys that are used, the more the MA (Mechanical Advantage). Copyright © 2010 Ryan P. Murphy
  63. 63.  The more pulleys that are used, the more the MA (Mechanical Advantage). Copyright © 2010 Ryan P. Murphy
  64. 64.  MA = The number of ropes that support the pulley. The end of the rope doesn’t count.  What is the MA of this pulley system below? Copyright © 2010 Ryan P. Murphy
  65. 65. • MA = The number of ropes that support the pulley. The end of the rope doesn’t count. – What is the MA of this pulley system below? Copyright © 2010 Ryan P. Murphy
  66. 66. • MA = The number of ropes that support the pulley. The end of the rope doesn’t count. MA =2 – What is the MA of this pulley system below? Copyright © 2010 Ryan P. Murphy
  67. 67. • MA = The number of ropes that support the pulley. The end of the rope doesn’t count. MA =2 – What is the MA of this pulley system below? Copyright © 2010 Ryan P. Murphy
  68. 68. • MA = The number of ropes that support the pulley. The end of the rope doesn’t count. MA =2 – What is the MA of this pulley system below? Copyright © 2010 Ryan P. Murphy FI =
  69. 69. • MA = The number of ropes that support the pulley. The end of the rope doesn’t count. MA =2 – What is the MA of this pulley system below? Copyright © 2010 Ryan P. Murphy FO FI
  70. 70. • MA = The number of ropes that support the pulley. The end of the rope doesn’t count. MA =2 – What is the MA of this pulley system below? Copyright © 2010 Ryan P. Murphy FO FI FI FO
  71. 71. • MA = The number of ropes that support the pulley. The end of the rope doesn’t count. MA =2 – What is the MA of this pulley system below? Copyright © 2010 Ryan P. Murphy FO FI FI FO 100 kg 50 kg
  72. 72. • MA = The number of ropes that support the pulley. The end of the rope doesn’t count. MA =2 – What is the MA of this pulley system below? Copyright © 2010 Ryan P. Murphy FO FI FI FO 100 kg 50 kg = 2 MA
  73. 73. • What is the MA of this pulley system? MA=2 Copyright © 2010 Ryan P. Murphy
  74. 74. • Answer, the MA is 4. Copyright © 2010 Ryan P. Murphy
  75. 75. • Answer, the MA is 4. Copyright © 2010 Ryan P. Murphy
  76. 76. • Answer, the MA is 4. Copyright © 2010 Ryan P. Murphy FI FO
  77. 77. • Answer, the MA is 4. Copyright © 2010 Ryan P. Murphy FI FO FI FO
  78. 78. • Answer, the MA is 4. Copyright © 2010 Ryan P. Murphy FI FO FI FO
  79. 79. • Answer, the MA is 4. Copyright © 2010 Ryan P. Murphy FI FO FI FO 100 25
  80. 80. • Answer, the MA is 4. Copyright © 2010 Ryan P. Murphy FI FO FI FO 100 25 = 4 MA
  81. 81. • What is the MA?
  82. 82. • What is the MA?
  83. 83. • What is the MA?
  84. 84. • What is the MA?
  85. 85. • What is the MA?
  86. 86. • What is the MA?
  87. 87. • What is the MA?
  88. 88. • What is the MA?
  89. 89. • What is the MA?
  90. 90. • Pulley Simulator: (Optional) – http://www.compassproject.net/sims/pulley.html
  91. 91.  Three types of pulleys  -  -  - Copyright © 2010 Ryan P. Murphy
  92. 92.  Fixed pulley  No MA Copyright © 2010 Ryan P. Murphy
  93. 93.  Fixed pulley  No MA Copyright © 2010 Ryan P. Murphy
  94. 94.  Movable Pulley (MA of 2) Copyright © 2010 Ryan P. Murphy
  95. 95.  Movable Pulley (MA of 2) Copyright © 2010 Ryan P. Murphy
  96. 96.  Combined Pulley / Block and tackle Copyright © 2010 Ryan P. Murphy
  97. 97. • Rock climbing uses pulleys. Copyright © 2010 Ryan P. Murphy
  98. 98. • Rock climbing uses pulleys. Copyright © 2010 Ryan P. Murphy
  99. 99. • Rock climbing uses pulleys. Copyright © 2010 Ryan P. Murphy
  100. 100. • Sailing uses pulleys to ease difficult jobs. Copyright © 2010 Ryan P. Murphy
  101. 101. Pulleys
  102. 102. • The chain on your bicycle is a pulley.
  103. 103. • Quiz Wiz 1-10 Fixed Pulley, Moveable Pulley, Block and Tackle/Combined Pulley Copyright © 2010 Ryan P. Murphy
  104. 104. • * Bonus: Name this family that used simple machines to create a tree house?
  105. 105. • Answers! Quiz Wiz 1-10 Fixed Pulley, Moveable Pulley, Block and Tackle/Combined Pulley Copyright © 2010 Ryan P. Murphy
  106. 106. • * Bonus: Name this family that used simple machines to create a tree house?
  107. 107. • * Bonus: Name this family that used simple machines to create a tree house?
  108. 108. • Activity! Using the three types of Pulleys Copyright © 2010 Ryan P. Murphy
  109. 109. • Activity! Using the three types of Pulleys Copyright © 2010 Ryan P. Murphy I wonder what the MA of this pulley system is?
  110. 110. • Activity! Using the three types of Pulleys Copyright © 2010 Ryan P. Murphy I wonder what the MA of this pulley system is?
  111. 111. • Activity! Using the three types of Pulleys Copyright © 2010 Ryan P. Murphy I wonder what the MA of this pulley system is?
  112. 112. Top Pulley Bottom Pulley
  113. 113. Top Pulley Bottom Pulley
  114. 114. Top Pulley Bottom Pulley
  115. 115. Top Pulley Bottom Pulley
  116. 116. Top Pulley Bottom Pulley
  117. 117. • Simple Machines Available Sheet.
  118. 118. Please create this spreadsheet in your journal. Weight (g) newtons No Pulley ____ grams Fixed Pulley ____ grams Combined Pulley 2 ____ grams Combined Pulley 4 ____ grams Copyright © 2010 Ryan P. Murphy
  119. 119. • Please use the materials to do the following. –Measure the newtons required with a Spring Scale to lift the ____ grams of weight with the different pulleys described in the spreadsheet. Copyright © 2010 Ryan P. Murphy
  120. 120. • Please use the materials to do the following. –Measure the newtons required with a Spring Scale to lift the ____ grams of weight with the different pulleys described in the spreadsheet. Copyright © 2010 Ryan P. Murphy Remember to zero your spring scale!
  121. 121. • Please use the materials to do the following. – Record the newtons required with a Spring Scale to lift the ____ grams of weight with a fixed pulley.
  122. 122. • Fixed Pulley System Construction
  123. 123. • Fixed Pulley System Construction
  124. 124. • Fixed Pulley System Construction
  125. 125. • Fixed Pulley System Construction
  126. 126. • Fixed Pulley System Construction
  127. 127. • Fixed Pulley System Construction
  128. 128. • Fixed Pulley System Construction
  129. 129. • Please use the materials to do the following. –Record the newtons with a combined pulley to lift the weight? Spring Scale Copyright © 2010 Ryan P. Murphy
  130. 130. • Two Pulley System Construction
  131. 131. • Two Pulley System Construction
  132. 132. • Two Pulley System Construction
  133. 133. • Two Pulley System Construction
  134. 134. • Two Pulley System Construction
  135. 135. • Two Pulley System Construction
  136. 136. • Two Pulley System Construction
  137. 137. • Two Pulley System Construction
  138. 138. • Please use the materials to do the following. – Record newtons with a combined pulley (4) to lift the ____ grams of weight?
  139. 139. • 4 Pulley System Construction
  140. 140. • 4 Pulley System Construction
  141. 141. • 4 Pulley System Construction Two wheels / Pulley
  142. 142. • 4 Pulley System Construction Two wheels / Pulley
  143. 143. • 4 Pulley System Construction
  144. 144. • 4 Pulley System Construction
  145. 145. • If you don’t have double pulleys, you can still use 4 single pulley’s like so. Copyright © 2010 Ryan P. Murphy
  146. 146. • Create a moveable pulley to lower the ___ gram weight into the bucket without touching it. Copyright © 2010 Ryan P. Murphy
  147. 147. • Questions? – What was the advantage in newtons to use a fixed pulley rather than no pulley at all? – What was the advantage in Newtons to use a combined pulley over a fixed pulley? – What was the advantage in Newtons to use a combined pulley (4) over a combined pulley (2)? – Did a moveable pulley allow you to move the load with minimal effort? Copyright © 2010 Ryan P. Murphy
  148. 148. • Questions? – What was the advantage in newtons to use a fixed pulley rather than no pulley at all? – What was the advantage in newtons to use a combined pulley over a fixed pulley? – What was the advantage in Newtons to use a combined pulley (4) over a combined pulley (2)? – Did a moveable pulley allow you to move the load with minimal effort? Copyright © 2010 Ryan P. Murphy
  149. 149. • Questions? – What was the advantage in newtons to use a fixed pulley rather than no pulley at all? – What was the advantage in newtons to use a combined pulley over a fixed pulley? – What was the advantage in newtons to use a combined pulley (4) over a combined pulley (2)? – Did a moveable pulley allow you to move the load with minimal effort? Copyright © 2010 Ryan P. Murphy
  150. 150. • Questions? – What was the advantage in newtons to use a fixed pulley rather than no pulley at all? – What was the advantage in newtons to use a combined pulley over a fixed pulley? – What was the advantage in newtons to use a combined pulley (4) over a combined pulley (2)? – Did a moveable pulley allow you to move the load with minimal effort? Copyright © 2010 Ryan P. Murphy
  151. 151. Weight (g) Newton No Pulley ___ grams 5 newtons Fixed Pulley ___ grams 5 newtons? Combined Pulley 2 ___ grams 3 newtons? Combined Pulley 4 ___ grams 1 newtons? Copyright © 2010 Ryan P. Murphy
  152. 152. • Questions? – What was the advantage in newtons to use a fixed pulley rather than no pulley at all? Copyright © 2010 Ryan P. Murphy
  153. 153. • Questions? – What was the advantage in newtons to use a fixed pulley rather than no pulley at all? – There was no Mechanical Advantage (MA) when using the fixed pulley. It was easier because you didn’t have to bend down. Copyright © 2010 Ryan P. Murphy
  154. 154. • Questions? – What was the advantage in newtons to use a combined pulley over a fixed pulley? Copyright © 2010 Ryan P. Murphy
  155. 155. • Questions? – What was the advantage in newtons to use a combined pulley over a fixed pulley? – The combined pulley required less force (2 newtons) to lift the load. The Mechanical Advantage was 2 newtons. Copyright © 2010 Ryan P. Murphy
  156. 156. • Questions? – What was the advantage in newtons to use a combined pulley (4) over a combined pulley (2)? Copyright © 2010 Ryan P. Murphy
  157. 157. • Questions? – What was the advantage in newtons to use a combined pulley (4) over a combined pulley (2)? – The (MA) was 4. It only took 1 newton to lift the load compared 3 newtons with the combined 2 pulley, and 5 newtons with no pulley at all. Copyright © 2010 Ryan P. Murphy
  158. 158. Pulleys. Learn more at… http://www.swe.org/iac/lp/pulley_03.html
  159. 159. • Questions? – Did a moveable pulley allow you to move the load with minimal effort? Copyright © 2010 Ryan P. Murphy
  160. 160. • Questions? – Did a moveable pulley allow you to move the load with minimal effort? – The pulley moved along the rope very easily. We were able to move the load easily once it was lifted. The pulley rolled down the rope because of it’s potential energy. • Not very good for lifting. Copyright © 2010 Ryan P. Murphy
  161. 161. • http://sciencepowerpoint.com/
  162. 162. Areas of Focus within The Motion and Machines Unit: Newton’s First Law, Inertia, Friction, Four Types of Friction, Negatives and Positives of Friction, Newton’s Third Law, Newton’s Second Law, Potential Energy, Kinetic Energy, Mechanical Energy, Forms of Potential to Kinetic Energy, Speed, Velocity, Acceleration, Deceleration, Momentum, Work, Machines (Joules), Catapults, Trajectory, Force, Simple Machines, Pulley / (MA Mechanical Advantage), Lever / (MA), Wedge / (MA), Wheel and Axle (MA), Inclined Plane / (MA), Screw / (MA) - Mousetrap Cars Full unit can be found at… http://sciencepowerpoint.com/Newtons_Laws_Motion_Machines_ Unit.html
  163. 163. • This PowerPoint is one small part of my Laws of Motion and Simple Machines Unit. • This unit includes… • A 3 Part 2,300+ Slide PowerPoint and student version. • 15 Page bundled homework package and 11 pages of units notes that chronologically follow the PowerPoint • 3 PowerPoint review games (150+ slides easch), 20+ Videos / Links, rubrics, games, activity sheets, and much more. • http://sciencepowerpoint.com/Newtons_Laws_Motion_M achines_Unit.html
  164. 164. http://www.teacherspayteach ers.com/Product/Physical- Science-Curriculum-596485 http://www.teacherspaytea chers.com/Product/Life- Science-Curriculum-601267 http://www.teacherspaytea chers.com/Product/Earth- Science-Curriculum-590950
  165. 165. • Please visit the links below to learn more about each of the units in this curriculum – These units take me about four years to complete with my students in grades 5-10. Earth Science Units Extended Tour Link and Curriculum Guide Geology Topics Unit http://sciencepowerpoint.com/Geology_Unit.html Astronomy Topics Unit http://sciencepowerpoint.com/Astronomy_Unit.html Weather and Climate Unit http://sciencepowerpoint.com/Weather_Climate_Unit.html Soil Science, Weathering, More http://sciencepowerpoint.com/Soil_and_Glaciers_Unit.html Water Unit http://sciencepowerpoint.com/Water_Molecule_Unit.html Rivers Unit http://sciencepowerpoint.com/River_and_Water_Quality_Unit.html = Easier = More Difficult =  5th – 7th grade 6th – 8th grade
  166. 166. Physical Science Units Extended Tour Link and Curriculum Guide Science Skills Unit http://sciencepowerpoint.com/Science_Introduction_Lab_Safety_Metric_Methods. html Motion and Machines Unit http://sciencepowerpoint.com/Newtons_Laws_Motion_Machines_Unit.html Matter, Energy, Envs. Unit http://sciencepowerpoint.com/Energy_Topics_Unit.html Atoms and Periodic Table Unit http://sciencepowerpoint.com/Atoms_Periodic_Table_of_Elements_Unit.html Life Science Units Extended Tour Link and Curriculum Guide Human Body / Health Topics http://sciencepowerpoint.com/Human_Body_Systems_and_Health_Topics_Unit.html DNA and Genetics Unit http://sciencepowerpoint.com/DNA_Genetics_Unit.html Cell Biology Unit http://sciencepowerpoint.com/Cellular_Biology_Unit.html Infectious Diseases Unit http://sciencepowerpoint.com/Infectious_Diseases_Unit.html Taxonomy and Classification Unit http://sciencepowerpoint.com/Taxonomy_Classification_Unit.html Evolution / Natural Selection Unit http://sciencepowerpoint.com/Evolution_Natural_Selection_Unit.html Botany Topics Unit http://sciencepowerpoint.com/Plant_Botany_Unit.html Ecology Feeding Levels Unit http://sciencepowerpoint.com/Ecology_Feeding_Levels_Unit.htm Ecology Interactions Unit http://sciencepowerpoint.com/Ecology_Interactions_Unit.html Ecology Abiotic Factors Unit http://sciencepowerpoint.com/Ecology_Abiotic_Factors_Unit.html
  167. 167. • The entire four year curriculum can be found at... http://sciencepowerpoint.com/ Please feel free to contact me with any questions you may have. Thank you for your interest in this curriculum. Sincerely, Ryan Murphy M.Ed www.sciencepowerpoint@gmail.com
  168. 168. • http://sciencepowerpoint.com/

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