The voltage V (in volts) across a resistor in an electric circuit is the product of the resistance and the current. If the current I (in A) varies with time (in s) according to and the resistance varies with time according to the relation R = 15.3 - 0.08t find the time rate of change of the voltage the relation I = 5.4 + 0.03t2 when t = 3 s