If a current of $8 \ A$ flows through a heater wire,what is the number of electrons passing through it in one minute?

The charge flowing in a conductor varies with time as $Q = at - bt^2$. Then for current,which statement is incorrect?
$(A)$ decreases linearly with time
$(B)$ reaches a maximum and then decreases
$(C)$ falls to zero after time $t = a/2b$
$(D)$ changes at a rate $-2b$

An electron revolves $6 \times 10^{15}$ times per second in a circular loop. The current in the loop is:

The current in a wire varies with time according to the relation $I = 4 + 2t$. The quantity of charge which has passed through a cross-section of the wire during the time $t = 2 \, s$ to $t = 6 \, s$ will be .............. $C$.

The current in a conductor varies with time $t$ as $I = 2t + 3t^2$,where $I$ is in ampere and $t$ is in seconds. The electric charge flowing through a section of the conductor during $t = 2 \, s$ to $t = 3 \, s$ is ............. $C$.

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 $C$)