Answer:
1. d = 0.415 m.
2. Q = 2.285 x 10^{-10} C.
Explanation:
The electric field and potential can be found by the following equations:

Applying these equations to the given variables yields

Divide the first line to the second line:

Using this distance in either of the equations give the magnitude of the charge.

Answer:
1 feet
Explanation:
Frame width = x
The length of the frame will be
(bottom and top that is why x is added twice)

The width of the frame will be

Area is given by

Solving the above equation we get

Hence width of the frame is 1 ft
c. energy and object has.....
Answer:
454,320 joules
Explanation:
The work done on an object is equal to its change in kinetic energy: Change in KE = F × d.
Plug the values for F and d into the formula and solve:
Change in KE = 2,524 × 180
= 454,320 joules
The roller coaster gains 454,320 joules of energy from the work done on it by the chain.