The resistance in an electric circuit varies inversely with the current. If the resistance is 12 ohms when the current is 4 amps, what is the resistance when the current is 8 amps.?

Answer 1

R = kI, where k is a constant.
put in the given values
12 = k(4)
k = 3

Now you have your equation to answer the last part

Answer 2

21

Answer 3

A