Which of the following reagents is the correct sequence for the conversion of $R-CH_2-CH_2OH$ to $R-CH_2-CH_2-COOH$?

What is the name of the reaction: $CH_3-CH=CH_2 \xrightarrow{CO + H_2O, H^+} CH_3-CH(COOH)-CH_3$?

Which of the following processes can be used to oxidize toluene to benzoic acid?

An alkyl bromide $X$ $(C_5H_{11}Br)$ undergoes hydrolysis in a two-step mechanism. $X$ is converted to a Grignard reagent and then reacted with $CO_2$ in dry ether followed by acidification to give $Y$. What is $Y$?

Find product $V$ in the following reaction sequence:
$CH_3-CH(CH_3)-COOH$ $\xrightarrow[H_3O^{+}]{LiAlH_4} I$ $\xrightarrow{PBr_3} II$ $\xrightarrow[ether]{Mg} III$ $\xrightarrow{CO_2} IV$ $\xrightarrow{H_3O^{+}} V$

Which of the following reaction sequences converts $R-CH_2CH_2OH$ into $R-CH_2CH_2COOH$?