Total number of reactions in which carboxylic acid is obtained as a product is
(a) \(\mathrm{R}-\mathrm{Cl} \frac{\text { (i) } \mathrm{Mg}}{\text { (ii) }
\mathrm{CO}_{2}}\)
(b) \(\mathrm{R}-\mathrm{Cl} \frac{\text { (i) } \mathrm{KCN}}{\text { (ii) }
\mathrm{H}_{3} \mathrm{O}^{+}}\)
(c) \(\mathrm{R}-\mathrm{CHO} \frac{\mathrm{CrO}_{3}}{\mathrm{H}_{2}
\mathrm{SO}_{4}}{\longrightarrow}\)
(d) \(\mathrm{R}-\mathrm{C}-\mathrm{Cl} \stackrel{\mathrm{H}_{3}
\mathrm{O}^{+}}{\longrightarrow}\)
(e) \(\mathrm{R}-\mathrm{CH}_{2} \mathrm{OH}
\frac{\mathrm{CrO}_{3}}{\mathrm{H}_{2} \mathrm{SO}_{4}}\)
(f) \(\mathrm{R}-\mathrm{CHO} \stackrel{\mathrm{Ag}_{2}
\mathrm{O}}{\longrightarrow}\)
(g) \(\mathrm{R}-\mathrm{NC} \stackrel{\mathrm{H}_{3}
\mathrm{O}^{+}}{\longrightarrow}\)