Answer:50.39 m/s,
40.46 m
Explanation:
Given
launch angle
Range=240 m
We know that Range 

u=50.39 m/s
(b)maximum height of projectile is given by


H=40.46 m
The energy that generates wind on an individual basis originates with
one's habitual diet. On a world-wide basis, it comes from the sun.
The correct answer is D He could pull the mass down farther.
Amplitude, is the maximum displacement or distance moved by a point on a vibrating body or wave measured from its equilibrium position. So to increase the amplitude the spring should be pulled down further which can increase the amplitude.
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 