To develop this problem it is necessary to apply the concepts related to Gravitational Potential Energy.
Gravitational potential energy can be defined as

As M=m, then

Where,
m = Mass
G =Gravitational Universal Constant
R = Distance /Radius
PART A) As half its initial value is u'=2u, then



Therefore replacing we have that,

Re-arrange to find v,



Therefore the velocity when the separation has decreased to one-half its initial value is 816m/s
PART B) With a final separation distance of 2r, we have that

Therefore




Therefore the velocity when they are about to collide is 
Answer:
Explanation:
Given dish width= 48ft
Depth = 4ft
Using equation of a parabola
x²= 4py
48² = 4p 4
4p = 576
P= 144ft
Thus the the receiver should be placed 144ft from t the vertex
Explanation:
The somatic nervous system coordinates the voluntary control of movement in the body system.
The nervous system is made up of the central nervous system and peripheral nervous system.
The peripheral nervous system is made up of the nerves that branches into the body from the spinal cord.
- It consist of the somatic nervous system and the autonomous nervous system.
- The somatic nervous system controls the voluntary actions of movement in the body.
- It coordinates the reflex arc.
Learn more:
Nervous system brainly.com/question/4662759
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