If the half-life of a reaction is halved when the initial concentration of the reactant is doubled,what is the order of the reaction?

The following results have been obtained during the kinetic studies of the reaction: $2 \ NO + 2 \ H_2 \longrightarrow N_2 + 2 \ H_2O$

Expt	$\frac{-d[NO]}{dt} \ (mol \ L^{-1} \ s^{-1})$	$[NO] \ (mol \ L^{-1})$	$[H_2] \ (mol \ L^{-1})$
$1$	$4.8 \times 10^{-5}$	$1 \times 10^{-2}$	$1 \times 10^{-3}$
$2$	$43.2 \times 10^{-5}$	$3 \times 10^{-2}$	$1 \times 10^{-3}$
$3$	$86.4 \times 10^{-5}$	$3 \times 10^{-2}$	$2 \times 10^{-3}$

The rate of a reaction depends upon the

Reaction : $2Br^{-} + H_2O_2 + 2H^{+} \to Br_2 + 2H_2O$
takes place in two steps :
$(a)$ $Br^{-} + H^{+} + H_2O_2 \xrightarrow{slow} HOBr + H_2O$
$(b)$ $HOBr + Br^{-} + H^{+} \xrightarrow{fast} H_2O + Br_2$
The order of the reaction is

The rate law for the reaction $A + B \rightarrow P$ is given by $\text{rate} = k[A]^2[B]$. The rate constant of the reaction at $300 \text{ K}$ is $6.0 \text{ M}^{-2} \text{s}^{-1}$. Calculate the rate of the reaction when $[A] = 1 \text{ M}$ and $[B] = 0.2 \text{ M}$. (in $\text{ M s}^{-1}$)

Ozone decomposes into oxygen as follows:
$O_3 \rightleftharpoons O_2 + [O]$
$O_3 + [O] \to 2O_2$ (slow)
Determine the order of the reaction $2O_3 \to 3O_2$.