Electric current is passing uniformly through a solid cylindrical wire of radius $R$. The current $i$ passing through circular cross-section of radius $r$ measured from the axis of the cylinder $(r<R)$ varies as shown in

The current $i$ through a conductor varies with time $t$ as shown in figure. The average electric current during $t=0$ to $t=10 \mathrm{s}$ will be

In the circuit shown, the current drawn by the cell is

In the situation shown each cell has e.m.f. $4 \mathrm{V}$ and internal resistance $1\mathrm{\Omega }$. The maximum power that can be delivered to the variable load resistance $R$ is