Which compound gives acetaldehyde upon reaction with aqueous $KOH$?

When chloroform is treated with conc. $HNO_3$,it gives:

What is the product obtained when $trans-2-phenyl-1-bromocyclopentane$ is treated with alcoholic $KOH$?

Reaction of $(R)-2$-butanol with $p$-toluenesulphonyl chloride in pyridine followed by reaction with $LiBr$ gives

What are $X, Y$ and $Z$ in the following reactions?
$(CH_3)_3 C-O^- Na^+ + CH_3 CH_2 Br \longrightarrow X + NaBr$
$(CH_3)_3 C-Br + CH_3 CH_2 O^- Na^+ \longrightarrow Y + Z$

The reaction of a mixture of two alkyl halides with sodium in ether gives $2-$methylpropane. The alkyl halides are: