Half life of a zero order reaction is directly proportional to $\qquad$

The concentration of $R$ in the reaction $R \rightarrow P$ was measured as a function of time and the following data is obtained:

$[R] \text{ (molar)}$	$1.0$	$0.75$	$0.40$	$0.10$
$t \text{ (min.)}$	$0.0$	$0.05$	$0.12$	$0.18$

The order of the reaction is:

$A$ zero-order reaction,$A \rightarrow \text{Product}$,with an initial concentration $[A]_0$ has a half-life of $0.2 \ s$. If one starts with the concentration $2[A]_0$,then the half-life is $.... \ s$

What is the formula to find the value of $t_{1/2}$ for a Zero Order Reaction?

For a zero-order reaction,the correct expression for rate constant $(k)$ at half-life time $(t_{1/2})$ is ($[R_0] =$ initial concentration of reactant).

The rate constant for a zero order reaction is $2 \times 10^{-2} \ mol \ L^{-1} s^{-1}$. If the concentration of the reactant after $25 \ s$ is $0.5 \ M$,the initial concentration must have been $:-$ (in $M$)