Question

You can do only number 1 only

Answer 1

After rearranging the formula Q = It, to find for time, the new formula would be:
t = Q / I
From question:
Q = 100C
I = 0.1A

Therefore, time, t = 100 / 0.1 = 1000 s

Answer 2

For 1000 seconds , a current of 0.1 A flows so as to transfer charge of 100C