Provide the missing product in the following reaction:
$CH_3-CH=CH-CH_2OH \xrightarrow{PCC} (?)$

$CH_3-C(CH_3)(OH)-C(CH_3)(OH)-CH_3 \xrightarrow[H^{+}]{\Delta} ?$

The correct set of reagents which convert acetylene to but$-2-$enal are

Identify the reagent used in the following conversion: $\text{Pent-3-enenitrile} \xrightarrow{A} \text{Pent-3-enal}$

In the reaction $CH_3CN + 2H \underset{\text{Ether}}{}$ ${\xrightarrow{HCl}} X$ $\xrightarrow{\text{Boiling } H_2O} Y$; the product $Y$ is

Give names of the reagents to bring about the following transformations:
$(i)$ $\text{Hexan-}1\text{-ol}$ to $\text{hexanal}$
$(ii)$ $\text{Cyclohexanol}$ to $\text{cyclohexanone}$
$(iii)$ $p\text{-Fluorotoluene}$ to $p\text{-fluorobenzaldehyde}$
$(iv)$ $\text{Ethanenitrile}$ to $\text{ethanal}$
$(v)$ $\text{Allyl alcohol}$ to $\text{propenal}$
$(vi)$ $\text{But-}2\text{-ene}$ to $\text{ethanal}$