Answer:
The final velocity is 
Explanation:
From the question we are told that
The mass of the child is 
The initial speed of the child is 
The mass of the wagon is 
The initial speed of the wagon is 
The mass of the ball is 
The initial speed off the ball is 
Generally the initial speed of the system (i.e the child , wagon , ball) is

Generally from the law of linear momentum conservation

Here
is the momentum of the system before the ball is dropped which is mathematically represented as

=> 
=> 
and
is the momentum of the system after the ball is dropped which is mathematically represented as

=> 
So

=> 
The answer would be Power
Answer:
the rocks are away from cracks in the crust
Explanation:
The new crust is pushed away from the Ocean Ridge in both directions as newer crust is formed. This is called sea floor spreading. The crust that makes up the sea floor starts to have time to accumulate a layer of sediments as it gets older and moves away from the Ocean Ridge.
Answer: The body will be in a position of rest
Explanation:
Since both forces are equal and acting in opposite direction on the body. It will make the body to be in a state of rest or equilibrium because the sum of the forces acting in the body will be zero.
Explanation:
Given
initial velocity(v_0)=1.72 m/s

using 
Where v=final velocity (Here v=0)
u=initial velocity(1.72 m/s)
a=acceleration 
s=distance traveled

s=0.214 m
(b)time taken to travel 0.214 m
v=u+at


t=0.249 s
(c)Speed of the block at bottom

Here u=0 as it started coming downward

v=1.72 m/s