By definition, we have that the mechanical advantage is given by the following equation:

Where,
W: is the load
T: is the tension
Substituting the values in the given equation we have:

Therefore, the mechanical advantage is equal to 5.
Answer: The mechanical advantage of this machine is: MA = 5
Answer:
5.1*10^3 J/m^3
Explanation:
Using E = q/A*eo
And
q =75*10^-6 C
A = 0.25
eo = 8.85*10^-12
Energy density = 1/2*eo*(E^2) = 1/2*eo*(q/A*eo)^2 = [q^2] / [2*(A^2)*eo]
= [(75*10^-6)^2] / [2*(0.25)^2*8.85*10^-12]
= 5.1*10^3 J/m^3