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

The rate constant,$k$ of a zero order reaction $2 NH_{3(g)} \xrightarrow[1130 \ K]{Pt} N_{2(g)} + 3 H_{2(g)}$ is $y \times 10^{-4} \ mol \ L^{-1} \ s^{-1}$. The rate of formation of hydrogen (in $mol \ L^{-1} \ s^{-1}$) is

Which of the following is true for a zero order reaction?

The half-life for a zero order reaction having $0.02 \; M$ initial concentration of reactant is $100 \; s$. The rate constant (in $mol \; L^{-1} s^{-1}$) for the reaction is

What is the concentration (in $mol \ L^{-1}$) of the product $B$ after $20 \ s$ in the following reaction? Given that $A \longrightarrow 3B$,rate $= k[A]^0$. The data is provided in the table below:
| Time $(s)$ | Concentration of reactant $A$ $(mol \ L^{-1})$ |
| :--- | :--- |
| $0$ | $0.1$ |
| $15$ | $0.05$ |
| $20$ | $0.1 - x$ |

Which of the following statements is true?