In Figure, R = 15??, L = 5.0 H, the ideal battery has = 10 V

Question:

In Figure, R = 15??, L = 5.0 H, the ideal battery has ξ = 10 V and the fuse in the upper branch is an ideal 3.0 A fuse. It has zero resistance as long as the current through it remains less than 3.0 A. If the current reaches 3.0 A. the fuse "blows" and thereafter has infinite resistance. Switch S is closed at time t = 0.

(a) When does the fuse blow?

(b) Sketch a graph of the current i through the inductor as a function of time. Mark the time at which the fuse blows.