Time taken to complete a zero order reaction is . . . . . . .

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 $0.25 \ M$?

Which of the following is a zero order reaction?

What is the correct relation between rate constant and half-life for a zero order reaction?

At $T \ K$,if the rate constant for a zero order reaction is $2.5 \times 10^{-3} \ M \ s^{-1}$,the time required for the initial concentration of reactant $R$ to fall from $0.10 \ M$ to $0.075 \ M$ at the same temperature in seconds is:

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 ........ $hr$.