Your science teacher has just asked you to solve some problems using dimensional analysis….OMG! What is dimensional analysis??
Don't sweat it! Dimensional Analysis (DA) is just a fancy term for converting one unit to another.
You use dimensional analysis in all the sciences from biology to chemistry and physics. You use DA anytime you need to convert one unit to another unit.
Just think "measurements need to have two parts - a number and a unit". For example, if you said "My heart beats 60" that would make no sense! Do you mean 60 beats per second or 60 beats per minute? At 60 beats per second you are probably in good health. But at 60 beats per minute, you could be a very sick person!
That's why measurements in science are composed of two parts - the quantity or numerical part and the dimension. The dimension can be time and distance, length, weight and mass, temperature, area, etc