$$ \text { What are the correct structural descriptions for } M \text { and } N \text { ? } $$

Consider an exothermic reaction: $2 \mathrm{~A}(\mathrm{~s}) \rightarrow \mathrm{B}(\mathrm{s})+\mathrm{C}(\mathrm{g})+\mathrm{D}(\mathrm{g})$. The correct statement about the reaction is

The minimum energy needed to remove an electron from a metal corresponds to a wavelength of 500 nm . What is the total kinetic energy of all the photoelectrons ejected per second when the entire radiation from a 100 Watt bulb with a wavelength of 300 nm falls on the surface of the metal? [Planck's constant $=6.6 \times 10^{34} \mathrm{Js}$; speed of light $=3 \times 10^8 \mathrm{~ms}^{-1}$ ]

For a reaction $R \rightarrow P$ with a rate constant of $3 \times 10^{-3} \mathrm{~mol} \mathrm{~L}^{-1} \mathrm{~s}^{-1}$, which one of the following plots is correct? (Given [R] $]_0$ is the initial concentration of $R$ and $[R]$ is the concentration of $R$ at time t)