Answer: The change in velocity is 20mph
Explanation: The change in velocity is the difference between the final velocity and the initial velocity.
The initial velocity is 0 and the final velocity is 20mph.
Using the formula dV=Vf-Vi
dV=20-0
dV=20mph North
Answer:
A
B

C

D

Explanation:
Considering the first question
From the question we are told that
The spring constant is 
The potential energy is 
Generally the potential energy stored in spring is mathematically represented as 
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=>
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Considering the second question
From the question we are told that
The mass of the dart is m = 0.050 kg
Generally from the law of energy conservation

=> 
=> 
Considering the third question
The height at which the dart was fired horizontally is 
Generally from the law of energy conservation

Here KE is kinetic energy of the dart which is mathematical represented as

=> 
=> 
=> 
Considering the fourth question
Generally the total time of flight of the dart is mathematically represented as

=> 
=> 
Generally the horizontal distance from the equilibrium position to the ground is mathematically represented as

=> 
=> 
They made me do it I don’t even know what to say I’m so sorry