A V = 86-V source is connected in series with an R = 1.89-k resistor and an L = 26-H inductor and the current is allowed to reach maximum. At time t = 0 a switch is thrown that disconnects the voltage source, but leaves the resistor and the inductor connected in their own circuit. After the current decreases to 53 % of its maximum value, the battery is reconnected into the circuit by reversing the switch.

(a) At what value of the time t, in milliseconds, does the current reach 74 % of its maximum?

(b) How much energy, in millijoules, is supplied in total by the battery, both in initially bringing the current to maximum and in bringing the current back to the 74 % level from 53 %? Ignore energy dissipated in the resistor during those processes.