<span>the scientific study of the human mind and its functions..</span>
X-rays have the shortest wavelength of any waves on that particular list.
Gamma ray waves are shorter than X-rays, but they're not on that list.
Answer:
a) 
b) 
c)
d) 
Explanation:
Given:
- mass of the astronaut,

- vertical displacement of the astronaut,

- acceleration of the astronaut while the lift,

a)
<u>Now the force of lift by the helicopter:</u>
Here the lift force is the resultant of the force of gravity being overcome by the force of helicopter.

where:
force by the helicopter
force of gravity


b)
The gravitational force on the astronaut:



d)
Since the astronaut has been picked from an ocean we assume her initial velocity to be zero, 
using equation of motion:



c)
Hence the kinetic energy:



Answer:
The greatest force of gravity on the ball will occur at the point when the ball is near to hit the ground
Explanation:
We know that the earth's center attracts everything towards its center with an acceleration of 9.8 m/s² so it simply means that the change in velocity must occur to produce acceleration. When the ball comes towards the earth, its speed continuously increases and it is at maximum level when it is about to hit the ground so this is the point where gravitational force is maximum.
I hope this helps ^_^