Answer:

(iii) > (ii) > (iv) > (i)

Explanation:

Stability of carbocation : 3° > 2° > 1°

Bridge Head carbocation i. e. (i) here are not generally stable

(iii) is 3°

(ii) is 2°

(i) is 1°

Therefore answer is (iii) > (ii) > (iv) > (i)

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