Acircuit carries a current of 0.64 a when there is a resistance of 50.0 ω. the voltage applied to the circuit, to the nearest whole number, is v.

The relationship between current and voltage within a direct current circuit is known as Ohm's law. The equation that relates voltage (V), current (I) and resistance (R) is V=IR. In this case  I=0.64 Amps and R=50 Ohms. Therefore the voltage is simply 0.64 multiplied by 50 and the answer is 32 Volts. The Ohm's law equation can also be rearranged in order to find current or resistance. 

Amplify and switch electrical power and electronic signals

Ithink the answer is c but then again i'm probably wrong