How will you bring ethanol to $3$-Hydroxybutanal conversion in not more than two steps?

How will you bring about the following conversion in not more than two steps?

Benzene to $\mathrm{m}$-Nitroacetophenone.

How will you bring about the following conversion in not more than two steps?

Benzaldehyde to Benzophenone.

How will you bring about the following conversion in not more than two steps?

Bromobenzene to $1$-Phenylethanol.

How will you bring about the following conversion in not more than two steps? 

Benzaldehyde to $3$-phenylpropan-$1$-ol.

How will you bring about the following conversion in not more than two steps?

Benzaldehyde to α-Hydroxyphenylacetic acid

How will you bring about the following conversion in not more than two steps? 

Benzoic acid to m-Nitrobenzyl alcohol

Describe the following: 

Cannizzaro reaction