the correct answer is B. 1.27
Mechanical advantage of a lever is simply the ratio of the effort arm to the load arm.Effort arm is the distance from the pivot to the point of application of force while load arm is the distance of the lord from the pivot.
therefore, in this question, the effort arm is 0.28m while the load arm is 0.22 m. MA is calculated as follows: MA=effort arm/load arm
=0.28m/0.22m=1.27
As we know that electrostatic force is a conservative force
so we can say by the condition of conservative force

here we can rearrange the above equation as

now integrate both sides

Now we know by the definition of work done by a force is given by

now work done by conservative force is given as

Now from above work done by electric field to move charge from one point to other is given as

so here work done is given as

so change in potential energy is given by work done
Answer:
The constant angular acceleration of the wheel is 12.16 rad/s²
Explanation:
Given;
initial angular distance, θ = 28
time of the motion, t = 5 s
initial angular velocity is calculated as;

final angular velocity is given as, 
The constant angular acceleration is calculated as;

Therefore, the constant angular acceleration of the wheel is 12.16 rad/s²
Energy and work hope it helps