Identify the reagent '$$A$$' used in the following conversion.

Ethyl bromide $$\stackrel{\mathrm{A}}{\longrightarrow}$$ Ethylpropanoate

Which among the following has the lowest boiling point?

Identify the product '$$\mathrm{B}$$' in the following reaction.

Dry ice $$\mathrm{\mathrel{\mathop{\kern0pt\longrightarrow} \limits_{Dry\,ether}^{C{H_3}MgBr}}}$$ A $$\mathrm{\mathrel{\mathop{\kern0pt\longrightarrow} \limits_{dil.\,HCl}^{{H_2}O}}}$$ B

Identify product '$$\mathrm{B}$$' in following reaction.

Cumene $$\xrightarrow[\Delta]{\mathrm{KMnO}_4, \mathrm{KOH}} \mathrm{A} \xrightarrow{\mathrm{H}_3 \mathrm{O}+} \mathrm{B}$$