What is the order of reaction if the unit of the rate constant is $s^{-1}$?

Half-life periods for a reaction at initial concentrations of $0.1 \ M$ and $0.01 \ M$ are $5$ and $50$ minutes,respectively. The order of reaction is

For the reaction $H_{2(g)} + Br_{2(g)} \rightarrow 2HBr_{(g)}$,the experimental data suggests the rate law is $\text{Rate} = K[H_2][Br_2]^{1/2}$. Find the order of the reaction and its molecularity.

What is the relationship between the half-life period $(t_{1/2})$ and the initial concentration $([R]_0)$ for a reaction of order $n$?

The reaction,$X + 2Y + Z \to N$ occurs by the following mechanism:
$(i)$ $X + Y \rightleftharpoons M$ (very rapid equilibrium)
$(ii)$ $M + Z \to P$ (slow)
$(iii)$ $P + Y \to N$ (very fast)
What is the rate law for this reaction?

Consider the following single step reaction in gas phase at constant temperature.
$2 \ A_{(g)} + B_{(g)} \rightarrow C_{(g)}$
The initial rate of the reaction is recorded as $r_1$ when the reaction starts with $1.5 \ atm$ pressure of $A$ and $0.7 \ atm$ pressure of $B$. After some time,the rate $r_2$ is recorded when the pressure of $C$ becomes $0.5 \ atm$. The ratio $r_1 : r_2$ is $\qquad$ $\times 10^{-1}$.
(Nearest integer)