(a) Give the decreasing order of stabilities of the following alkenes :
(i) Ethene,
(ii) Propene,
(iii) `cis-2-`butene
(iv) trans-2-Butene
(v) `2-`Methy1-2-butene,
(vi) `2,3-`Dimethy1-2-butene
(b) Give the decreasing order of reactivity of the above alkenes.
( c) Give the product of the following reaction :
`Me_(2)CHCH_(2)CH_(2)OH overset("Dehydration")underset("Conc"H_(2)SO_(4)(160-170^(@)C))rarrunderset(-H_(2)O)(A)`

Explanation

(a) `vi gt v gt iv gt iii gt i`
More substituted alkene is more stable.

(b) Reactivity order is reverse of stability.
`I gt ii gt iii gt iv gt v gt vi`
( c) .