Alkyl halide $\xrightarrow[\text{Ether}]{Mg}$ Grignard Reagent $\xrightarrow{H_2O}$ Propane,then alkyl halide may be :-

What is the major product obtained in the following reaction?

How will you bring about the following conversions?
$(i)$ Ethanol to but$-1-$yne
$(ii)$ Ethane to bromoethene
$(iii)$ Propene to $1-$nitropropane
$(iv)$ Toluene to benzyl alcohol
$(v)$ Propene to propyne
$(vi)$ Ethanol to ethyl fluoride
$(vii)$ Bromomethane to propanone
$(viii)$ But$-1-$ene to but$-2-$ene
$(ix)$ $1-$Chlorobutane to $n-$octane
$(x)$ Benzene to biphenyl.

In the following reaction sequence, $X$ and $Z$, respectively, are:
$CH_{3}CH_{2}CH_{2}-OH + PCl_{5} \rightarrow CH_{3}CH_{2}CH_{2}Cl + X + HCl$
$CH_{3}CH_{2}CH_{2}Cl \xrightarrow{alc. KOH, \Delta} Y$
$Y \xrightarrow{HBr, (C_{6}H_{5}CO)_{2}O_{2}} Z$

Which of the following products can be obtained from the above reaction?

The products obtained in the above reactions $(1)$,$(2)$,and $(3)$ are: