A mass is lifted vertically upward. Over time $t$, its gravitational potential energy increases by $E_p$ and its kinetic energy increases by $E_k$. What is the average power supplied to the mass?
- A$\dfrac{(E_p - E_k)}{t}$
- B$\dfrac{(E_p + E_k)}{t}$
- C$\dfrac{E_p - E_k}{t}$
- D$\dfrac{E_p + E_k}{t}$