In a first reaction 60% of reactant decomposes in 4.606 min. What is half life of reaction? (k = 0.1989 min$$^{-1}$$)

For the reaction, $$2 \mathrm{~A}+\mathrm{B} \rightarrow 2 \mathrm{C}$$, rate of disappearance of $$\mathrm{A}$$ is $$0.076 \mathrm{~mol} \mathrm{~s}^{-1}$$. What is the rate of disappearance of $$\mathrm{B}$$ ?

Half-life and rate constant for first order reaction are related by equation,

If decomposition of hydrogen peroxide is a first order reaction, it's rate law equation can be represented as