The passage summarizes the development of the de Havilland DH 106 Comet, which was the world's first commercial jet airliner. It started service in 1952 but numerous crashes due to structural failures led to the entire fleet being grounded in 1954. Extensive testing revealed flaws in the aircraft's structural design, which was later remedied. The improved Comet design had a productive career of over 30 years.

2. *Q1.
The de Havilland DH 106 Comet was the world's first production
commercial jet, which started services in 1952. The service was plagued
with hull losses from its inception and reached a dead end in 1954 when
the entire fleet was grounded after BOAC (British Overseas Airways
Corporation ) flight 781 plummeted to its doom, taking the lives of all 35
people on board.
The planes were subjected to extreme “water torture” tests to evaluate the
integrity of the fuselage, in a dedicated water tank that was built
specifically at Farnborough to accommodate its full length. It was found
the stress was unevenly distributed along the aircraft frame due to a
flawed structural design, which was later replaced by the design which is
commonplace today in all high altitude jetliners. The results from these
extensive reviews were used in the design revisions for the improved
Comet versions which had a productive career of over 30 years. What
feature was introduced thus ? Image follows.

4. Round / Oval windows

5. *Q2.
In the united States of America, the illegal production and
distribution of liquor or bootlegging as it is called is banned
by law. The law dictates that it is illegal to produce or
distribute alcohol that is meant for consumption from
petrochemical sources and that all liquor must be made from
the fermentation and processing of natural products like
grapes, grains or fruit which rules out alcohol produced from
petroleum, even though such alcohol is just as safe and tastes
no different from the real deal.
What ingenious and cost effective solution was developed by
the United States Bureau of Alcohol, Tobacco, Firearms and
Explosives, charged with enforcing the natural alcohol rule,
to determine the source of the alcohol in a product?

6. Check for Radioactivity(Carbon-14)

7. *Q3.What is blanked out from this XKCD comic?

8. Sudo command

9. Q4.
Give the funda. Bonus for filling the blank ;)

11. *Q5.
What has been blanked out in the picture ?

13. Q6.
This product is classified on the basis of three parameters in
the European system, which also followed in India.
In this degree scale of classification, Hardness is denoted by
H, the Fineness ( if applicable) is denoted by F, which
represents ‘Fine Point’ and the degree of Blackness is denoted
by B. The Alphabets are often preceded by a number which
also plays a significant role in denoting the quality of the
product, in either one of the parameters evaluated.
What product is being described here?

14. Pencils

15. Q7.
The medical term for this phenomenon is
Synchronous Diaphragmatic Flutter (SDF) or
singultus. It is an involuntary action that proceeds via a
reflex arc, which once triggered causes a strong
contraction of the diaphragm followed by the closure of
the vocal chords.
What is the ever so common phenomenon that all of us
has experienced at least once in our lives?

16. Hiccups

17. Q8.
Whose epitaph is shown in the picture ?

19. *Q9.
Comic parodying which experiment? Give me the name of the
phenomenon being studied or the name of the experimental
set-up .

20. Operant Conditioning/ Skinner box

21. On April 29th, 1975, at the age of 19, X was arrested by the
Albuquerque Police department (arrest record #52090). The
charges were speeding and driving without a license. It was
the first of three arrests in the late seventies by Albuquerque
Police. According to records, X was frequently caught
speeding in his Porsche 911.
That day, he was driving along with Paul Allen. Although he
was granted bail almost immediately for the minor offence,
the most famous consequence of the event is still doing its
rounds all over the internet. Who is the person or what
consequence?
Q10.

22. Bill Gates mugshot

23. Q11.
404 error message for which service ?

24. Dropbox

25. The most popular etymological explanation for the
name X is a French word which literally translates to
“Monk-Killer” which arises from the fact most early
alchemists were monks and X being poisonous would
have caused the death of many early experimentalists.
X is most commonly found as its sulphide mineral
Stibnite, which was used by early civilizations like
Egyptians as Kohl, and still continues to be in use.
Which element? Image follow.
Q12.

27. Antimony ( Sb)

28. Q13. *video

29. Oppenheimer on atomic bomb

30. *Q14. *video

31. Imprinting

32. Q15.
The X scale measures pungency in onions and garlic with
units of µm/gfw (micromoles per gram fresh weight). It is
named after Y acid, the alpha-keto acid in onions involved in
the process which makes peoples eyes tear up when cutting
them.
The standard brown onion has a rating between 6 and 7,
while “sweet onions” have a two or three rating on the scale.
The lower the score or scale, the more “sweet” the onions are
rated. Anything less than five is considered a sweet onion.
Soil type, rain and sunlight have been shown to affect the
rating of an onion on the X scale. Id X or Y.

33. Pyruvate / Pyruvic acid

34. Q16. *Video

35. Rube Goldberg Contraption

36. Q17. *Video

37. First demonstration of Television

38. Q18.Convallaria majalis is a sweetly scented but highly poisonous
flowering plant native to Asia and Europe. All parts of this plant are
highly poisonous including the red berries which children often
accidentally ingest due to its colorful appearance.
The flower is also known as Our Lady's tears or Mary's tears, which
arises from Christian legends that it sprang from the weeping of
the Virgin Mary during the crucifixion of Jesus. Other etiologies have its
coming into being from Eve's tears after she was driven with Adam from
the Garden of Eden or from the blood shed by Saint Leonard of
Noblac during his battles with a dragon.
In France, it is a tradition to sell flowers of X on 1st May (international
labour day) which is exempted from sales tax and is often associated
with the arrival of spring. X attained notoriety recently when a certain
baldy gentleman found great potential in its chemical subtleties. Id X
and the gentleman in Question. Images follow.

40. Lily of the Valley & Walter White

41. _________________is a phrase,
which was made popular due to a
1676 letter by Sir Isaac Newton,
although it has been since the 12th
century.
The phrase has had innumerable
references, ranging from books to
films to rock albums, but the most
famous one from a researcher’s
point of view would be the motto of
an acclaimed online tool.
X – Phrase,
Y - Tool …..
Q19.

43. Q20.
X is the name of the photograph shown, taken by
Voyager-1 in 1990, from a distance of 6 billion km.
It was taken at the request of Y, who pointed out that,
"all of human history has happened on that tiny pixel,
which is our only home“
What is the name of the photo (X) ?
Who is Y ?
Image follows.

45. Pale Blue Dot, Carl Sagan

46. Q21.
Since the late 1950s, aerospace engineers have used the
term “X" when referring to unusual or costly materials, or when
theoretically considering a material perfect for their needs in all
respects, except that it does not exist. By the 1990s, the term was in
wide use, even in formal engineering papers such as "Towards X
[new composite materials for space applications]."
The word X may well have been coined in the aerospace industry to
refer to materials capable of withstanding the extreme
temperatures expected in re-entry. Even though you might not
have heard of “X” in its formal usage, you would have heard of the
potential application of “X” as a room-temperature semiconductor
and the human conquest to gain access to this element by mining
for it on a fictional moon Y, in a 2009 blockbuster. Id X and Y.

47. Unobtanium (Unobtainium) , Pandora

48. *Q22.
Identify the scientists portrayed by these minimalist posters.

49. Rachel Carson, Grace Hopper

50. When X was offered a toast during the Nobel function, X
responded:
“Sir, you have seen the X effect on Y; please do not try to
see the Y effect on X”
Identify X and Y.
Q23.

51. Sir C V Raman, Alcohol ;)