Due to what is current formed in conductors?

$A$ steady current is flowing in a metallic conductor of non-uniform cross-section. The physical quantity which remains constant is

The charge flowing in a conductor changes with time as $Q(t) = \alpha t - \beta t^2 + \gamma t^3$. Where $\alpha, \beta$,and $\gamma$ are constants. The minimum value of current is:

$A$ current of $4.8\,A$ is flowing through a conductor. The number of electrons flowing per second is:

Current passing through a wire as a function of time is given as $I(t) = 0.02t + 0.01 \ A$. The charge that will flow through the wire from $t = 1 \ s$ to $t = 2 \ s$ is: (in $C$)

Estimate the magnitude of current that passes through a wire, if $0.1 \text{ mol}$ of electrons flow through it in $40 \text{ min}$. (Assume Avogadro number $= 6 \times 10^{23}$) (in $\text{ A}$)