Doubt from halides

#1

ques 4

#2

ques 13 and 14

#3

ques 17

#4

Q 14 B option
Q 4 b option

#5

Ques 4 b you are correct please give solution
And ques 14 c is given answer

#6

For Q 4 my approach was stronger the base , stronger is the nucleophile.
For Q 14 possible explanation can be that due to partial double character halides become weak leaving group.

#7

Q4)

#8

Q13)

#9

Q14)Due vacant d orbital in halides so they undergo resonance with double bond that’s why they double character.