Hello, I have the following question if anyone can help it would be greatly appreciated:

An inductor of negligible resistance and an inductance of 0.2 H is

connected in series with a 330 Ω resistor to a 12V d.c. supply.

Determine:

(a) the time constant of the circuit

(b) the voltage drop across the inductor after two time constants

(c) the voltage drop across the resistor after three time constants

(d) the resistance of a 0.2 H coil used to replace the inductor if the

circuit’s time constant falls to 0.55 ms.

I've attached my (rough!) answers, can anyone check if they agree please?

Thanks