Which of the following is a scalar quantity?

Define $1 \ Coulomb$ in terms of $1 \ Ampere$.

Define electric current and explain it. Write its $SI$ unit.

In an electrolyte,$3.2 \times 10^{18}$ bivalent positive ions drift to the right per second,while $3.6 \times 10^{18}$ monovalent negative ions drift to the left per second. Then the current is:

$A$ current of $20\,\mu A$ flows for $30$ seconds in a wire. The total charge transferred will be:

In a closed circuit,the current at time $t$ is given by $I = 4 - 0.08t$. The number of electrons passing through the cross-section of the conductor in $50 \ s$ will be: