Under a given set of experimental conditions,with an increase in the concentration of the reactants,the rate of a chemical reaction

For the reaction, $A + B \rightarrow P$, the rate law is $\text{rate} = k[A][B]^2$. The rate of reaction is $0.25 \text{ Ms}^{-1}$ when $[A] = 1 \text{ M}$ and $[B] = 0.2 \text{ M}$ at $25^\circ \text{C}$. Calculate the rate constant $k$ of the reaction at the same temperature.

For an $n^{th}$ order reaction where $n < 1$,what is the expression for the time required for $100\%$ completion $(t_{100\%})$?

In a reaction,if the concentration of reactant $A$ is tripled,the rate of reaction becomes twenty-seven times. What is the order of the reaction?

In the reaction,$P + Q \longrightarrow R + S$,the time taken for $75 \%$ reaction of $P$ is twice the time taken for $50 \%$ reaction of $P$. The concentration of $Q$ varies with reaction time as shown in the figure. The overall order of the reaction is

Match List-$I$ with List-$II$:

List-$I$ (Order of Reaction)	List-$II$ (Unit of rate constant)
$A$. Zero order	$I$. $mol^{-1} L s^{-1}$
$B$. First order	$II$. $mol^{-2} L^{2} s^{-1}$
$C$. Second order	$III$. $s^{-1}$
$D$. Third order	$IV$. $mol L^{-1} s^{-1}$