On what factor does the induced current depend?

The current $i$ in an inductance coil varies with time $t$ according to the following graph. Which one of the following plots shows the variations of voltage $V$ in the coil?

$A$ small bar magnet is moved through a coil at a constant speed from one end to the other. Which of the following series of observations will be seen on the galvanometer $G$ attached across the coil? Three positions shown describe: $(a)$ the magnet's entry,$(b)$ the magnet is completely inside,and $(c)$ the magnet's exit.

The network shown in the figure is part of a complete circuit. If at a certain instant,the current $I$ is $5 \ A$ and it is decreasing at a rate of $10^3 \ A \ s^{-1}$,then $V_B - V_A$ equals.....$V$.

The diagram below shows two coils $A$ and $B$ placed parallel to each other at a very small distance. Coil $A$ is connected to an ac supply. $G$ is a very sensitive galvanometer. When the key $K$ is closed:

The current $(I)$ in the inductance is varying with time according to the plot shown in the figure. Which one of the following is the correct variation of voltage $(V)$ with time in the coil?