What is the power dissipated by a 12 Ohm resistor when 2A of current run through it?

We know P=IV and that V=IR. Therefore as we are only given I and R in the question we can make the substitution for V so that P=I²R.
By plugging in the numbers we get: P=2²x 12= 48W
(W=Watts, unit of Power)