Both objects fall at the same speed. Mass does not affect the speed of falling objects, assuming there is only gravity acting on it.
This is a bit too broad. Maybe this is something to google up
3
velocity=wavelength(lander) ×frequency
let lander be x
v=12
f=3
12 =x4
x= 12/4
x=3
On Earth, none of the atmosphere is.
False, some adults will know more than your friends as they are already grown up and may have experienced the problem already
