Answer:
a)
, b)
, c) 
Explanation:
a) The change in the gravitational potential energy of the marble-Earth system is:


b) The change in the elastic potential energy of the spring is equal to the change in the gravitational potential energy, then:

c) The spring constant of the gun is:




Answer:
124.86 V
Explanation:
We have to first calculate the voltage drop across the copper wire. The copper wire has a length of 358 ft
1 ft = 0.3048 m
358 ft = 109.12 m
The diameter of 2 AWG copper wire (d) = 6.544 mm = 0.006544 m
The area of the wire = πd²/4 = (π × 6.544²)/4 = 33.6 mm²
Resistivity of wire (ρ) = 0.0171 Ω.mm²/m
The resistance of the wire = 
The voltage drop across wire = current * resistance = 6.1 A * 0.056 ohm = 0.34 V
The voltage at end = 125.2 - 0.34 = 124.86 V
I’m pretty sure the answer is A
I don’t know what the answer is to the question but if I don’t answer the question I will be mad at the