Ozonolysis of $2-$methyl$-2-$butene,in presence of $Zn,$ yields $--$

Identify the type of the given reactions:
$(a) \ CH_3CH_2OH \xrightarrow[\Delta]{\text{Conc. } H_2SO_4} CH_2 = CH_2 + H_2O$
$(b) \ CH_2BrCH_2Br + Zn \xrightarrow{\Delta} CH_2 = CH_2 + ZnBr_2$
$(c) \ CH_3CHBr - CH_2Br + Zn \xrightarrow{\Delta} CH_3CH = CH_2 + ZnBr_2$
$(d) \ RC \equiv CR' + H_2 \xrightarrow{Na, \text{liquid } NH_3} RCH = CHR'$
$(e) \ CH_3CH_2Cl + KOH \xrightarrow{\text{ethanol, } KOH} CH_2 = CH_2 + KCl + H_2O$

$A$ hydrocarbon $C_6H_{10}$ absorbs only one molecule of $H_2$ upon catalytic hydrogenation. Upon ozonolysis,it yields $CHO(CH_2)_4CHO$. What is the hydrocarbon?

The major product $(P)$ formed in the reaction below is: $HC \equiv C-CH_2-CH=CH_2 \xrightarrow[CCl_4, 253 \ K]{Br_2(1 \ mol)} P$

Ethylene reacts with bromine to form

An alkene gives two moles of $HCHO$,one mole of $CO_2$,and one mole of $CH_3COCHO$ on ozonolysis. What is its structure?