$A$ student has studied the decomposition of a gas $AB_3$ at $25^{\circ} C$. He obtained the following data.

$p \ (mm \ Hg)$	$50$	$100$	$200$	$400$
Relative $t_{1/2} \ (s)$	$4$	$2$	$1$	$0.5$

The order of the reaction is

The rate of reaction between two reactants $A$ and $B$ decreases by a factor of $4$ if the concentration of reactant $B$ is doubled. The order of this reaction with respect to reactant $B$ is

For the reaction $A + B \rightarrow$ products,it is observed that
$(i)$ on doubling the initial concentration of $A$ only,the rate of reaction is also doubled and
$(ii)$ on doubling the initial concentration of both $A$ and $B$,there is a change by a factor of $8$ in the rate of the reaction.
The rate of this reaction is given by

For a reaction,$A + B \longrightarrow$ Product; the rate law is given by $r = k[A]^2[B]^{1/2}$. What is the order of the reaction?

For the reaction $A + 2B \to C$,the rate equation is given as $\text{Rate} = K[A][B]$. If the concentration of $A$ is kept constant but that of $B$ is doubled,what will happen to the rate of the reaction?

If a reaction has the experimental rate expression $\text{rate} = K [A]^2[B]$,what happens to the reaction rate if the concentration of $A$ is doubled and the concentration of $B$ is halved?