$1\mathrm{.}32$ The voltage across and current through a certain device are

given by

$($t$)=100(1$ e$0\mathrm{.}2$t $)$ V

and

i$($t$)=60$e$0\mathrm{.}2$t mA$,$

respectively. Determine:

$($a$)$ The instantaneous power p$($t$)$ at t $=0$ and t $=3$ s$.$

$($b$)$ The cumulative energy delivered to the device from t $=0$ to

t $=$ $.$