Why is the probability of a reaction with molecularity higher than $3$ very rare?

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?

$A$ study of chemical kinetics of the reaction $A + B \to$ Products,gave the following data at $25 \ ^oC$.

$Exp. \ No.$	$[A]$	$[B]$	$Rate$
$1.$	$1.0$	$0.15$	$4.2 \times 10^{-6}$
$2.$	$2.0$	$0.15$	$8.4 \times 10^{-6}$
$3.$	$1.0$	$0.20$	$5.6 \times 10^{-6}$

Find out the rate law.

What is the order and molecularity of the following reaction?
$NO_{2(g)} + NO_{2(g)} \longrightarrow 2NO_{(g)} + O_{2(g)}$

The rate law for the reaction $A + B \rightarrow \text{product}$ is $\text{rate} = k[A][B]$. When will the rate of reaction increase by a factor of $2$?

State whether the following statements are true $(T)$ or false $(F)$.
$(a)$ In a pseudo first order reaction,the rate and rate constant are determined with respect to the reactant present in lower concentration.
$(b)$ The hydrolysis of an ester is carried out in the presence of an excess of water in an acidic medium.
$(c)$ The hydrolysis of an ester is a second order reaction.