A low-voltage source having an e.m.f. of $20\,\text{V}$ and an internal resistance of $1.5\,\Omega$ supplies a heater with resistance $6.5\,\Omega$ in a fish tank. What power is transferred to the water in the fish tank?
- A$41\,\text{W}$
- B$50\,\text{W}$
- C$53\,\text{W}$
- D$62\,\text{W}$