What is the number of moles of nascent hydrogen required to prepare 1 mole of methane from iodomethane?

Identify the product obtained in following reaction.

n $$\mathrm{CH}_3 \mathrm{MgI}+\mathrm{H}_2 \mathrm{O} \stackrel{\text { dry ether }}{\longrightarrow}$$ product

Which among the following is NOT a feature of $$\mathrm{S}_{\mathrm{N}} 2$$ mechanism?

What is the number of moles of secondary carbon atoms in $$\mathrm{n}$$ mole isopentane?