I'm not accurately sure if you're asking for why the bulb of a thermometer is in a cylindrical shape. So let me continue. The shape of the which is thin and cylindrical in the shape is the increase of the effect of mercury in the tube to rise and fall depending on the contact temperature.
The two will fall at the same speed and reach the surface at the same time. This is because the two will experience the same gravitational acceleration on the moon. However, on the earth surface the two will land on the surface of the earth at the same time due to air resistance such that the egg will experience a higher air resistance than the hammer. On, the moon, where there is no noticeable atmosphere there is no air resistance on either object and both fall at the same speed. It is also important to note that their mass doesn't affect their speed.
In my opinion, calling exercise "work" wouldn't be a good way of describing it, I don't think people would exercise if its called work
Answer: The IF clause.
Explanation: This is the IF clause; you can use it as:
IF (something = true) then "something happens"
else "other thing happens"
Some example of it can be, suppose that your program reads a number X that the user inputs, then you can do:
If ( X > 5) then
print: "the number X is bigger than five"
Else
print: "the number X is smaller than five"
Where, of course, the statements depend on the language used, but the "if" clause works almost the same in every language.