Answer:
Around 20 watts, or 19.4W exactly
Explanation:
to calculate the power in a time frame you use
Joules/Time(Seconds) = W (your power)
So, we take 3500 joules / 3min (180sec)
3500/180 = 19.4W, if your question asks you to round up/down, round up to 20W of power! good luck!
