What is the unit of $K$ for a zero-order reaction?

The reaction $2X \to B$ is a zeroth order reaction. If the initial concentration of $X$ is $0.2 \ M$,the half-life is $6 \ h$. When the initial concentration of $X$ is $0.5 \ M$,the time required to reach its final concentration of $0.2 \ M$ will be ........ $hr$.

Which of the following is correct with respect to the graph given?
$[R] = \text{Concentration at time } 't'$
$[R]_0 = \text{Initial concentration}$

For a zero order reaction,the plot of concentration $(a - x)$ $vs$ time is linear with

For a reaction $A \rightarrow$ products,the half-life period is $1 \ h$. The initial concentration of reactant $A$ is $2 \ M$. If this reaction is of zero order,how many hours will it take for the concentration of the reactant to decrease from $0.5 \ M$ to $0.25 \ M$?

Mention True $(T)$ and False $(F)$ statements for the following regarding a zero-order reaction $R \rightarrow P$:
$1. \ t_{1/2} \propto [R]_0$
$2. \ t_{1/2} \propto k$