For zero order reaction, a plot of $$t_{1 / 2}$$ versus $$[A]_0$$ will be

If the rate constant for a first order reaction is $$2.303 \times 10^{-3} \mathrm{~s}^{-1}$$. Find the time required to reduce $$4 \mathrm{~g}$$ of the reactant to $$0.2 \mathrm{~g}$$.