Which of the following reactions is used for the conversion of alkyl chloride to alkyl iodide?

Rank the following groups in order of decreasing leaving group ability:
$(i)$ $-OSO_2C_6H_4CH_3$ (tosylate)
(ii) $-OCOCH_3$ (acetate)
(iii) $-OCH_3$ (methoxide)
(iv) $-OSO_2CF_3$ (triflate)

Arrange the following alkyl halides in the increasing order of their reactivity towards nucleophilic substitution reaction:
$(I)$ $CH_3CH_2CH(Cl)CH_3$
$(II)$ $CH_2=CHCH(Br)CH_3$
$(III)$ $CH_2=CHCH(Cl)CH_3$
$(IV)$ $CH_3CH=C(Br)CH_3$

Iodoform on heating with $KOH$ gives

Which of the following compounds is formed when chloroform $(CHCl_3)$ is exposed to air and light?

What is the product formed when $CH_3-CH=CHBr$ reacts with $HBr$ in the presence of peroxide?