To draw maximum current from a combination of cells,how should the cells be grouped?

$A$ cell can supply currents of $1 \ A$ and $0.5 \ A$ via resistances of $2.5 \ \Omega$ and $10 \ \Omega$ respectively. The internal resistance of the cell is (in $\Omega$)

When two identical batteries of internal resistance $1 \Omega$ each are connected in series across a resistor $R$,the rate of heat produced in $R$ is $P_1$. When the same batteries are connected in parallel across $R$,the rate of heat produced is $P_2$. If $P_1 = 2.25 P_2$,then the value of $R$ is (in $\Omega$)

$N$ identical cells are connected in series or in parallel. When an external resistor $R$ is connected to them,they provide the same current. The internal resistance $r$ of each cell is:

The potential difference across a cell and the current through it are shown in the graph. $A$ battery consists of $40$ such identical cells. The maximum current supplied by the battery through a load of $2.5\,\Omega$ is equal to .............. $A$.

To get the maximum current from a parallel combination of $n$ identical cells,each of internal resistance $r$,connected to an external resistance $R$,which of the following conditions must be satisfied?