nI was given a graph of q/t which was an exponential decay I think.
The question said what was the current at
(i) t=0s
and
(ii) t=15s
for (i) I just put 0 as I have no idea how to start
for (ii) I worked out time of half-life(20s) and then subbed into the equation given to get 1.41x10-5A
the charge at 15s on the graph is 240x10-6 C not sure how to use it