Answer:
which agrees with the third answer in your list of answer options
Explanation:
Start with:

divide both sides by b to isolate c on the right:

Mechanical advantage is a measure of the force amplification achieved by using a tool.
Answer:
U = - 4 x 
Explanation:
ΔV = potential difference =
Volts
q = charge on electron =
C
electric potential energy is given as
U = q ΔV = (
) (
)
= - 4 x 
Change in temperature
A calorimeter directly measures temperature change and this information, along with the substance's mass and specific heat, is used to calculate the amount of heat.<span />