How can we measure the current in a circuit?

$A$ current of $1\, A$ is drawn by a filament of an electric bulb. The number of electrons passing through a cross-section of the filament in $16$ seconds would be roughly:

The amount of charge passing through a cell in $4 \, s$ is $12 \, C$. Find the current supplied by the cell. (in $, A$)

Identify the circuit (Figure) in which the electrical components have been properly connected.

The $SI$ unit of electric charge is $.........$

Which of the following combinations of cells in series (as shown in the figure) correctly represents the arrangement to obtain maximum potential?