The correct statements among the following regarding a balanced chemical equation of an elementary reaction are-

1. (a, b)
2. (b, c)
3. (c, d)
4. (a, d)

The correct graphical representation of first-order reaction is:

(a)		(b)
(c)		(d)

The slope of the given below graph is -

 $1.$ $\frac{\mathrm{k}}{2.303}$
$$
$2.$ $-\frac{\mathrm{k}}{2.303}$
$$
$3.$ $-\frac{2.303}{\mathrm{k}}$
$$
$4.$ $\frac{2.303}{\mathrm{k}}$

For a general reaction A → B, the plot of concentration of A vs time is given below:

The unit of the rate constant would be: