Verbal Reasoning - Mental Ability Questions

In the English alphabet, which letter is 13th from right end?

Ms. X's husband is the only son of Ms. Y's mother. If Ms. X's brother and Ms. Y's husband are cousins, then Ms. X is Ms. Y's ____.

Select the related word/letters/number from the given alternatives.
Frog : Amphibian : : Cobra : ?

In the following question, by using which mathematical operator will the expression become correct?
18 ? 6 ? 9 ? 27

Among four books, Book1 is twice as heavy as Book 2. Book 3's weight is half of Book 2's weight. Book 4 is 60 grams more as compared to Book 2 but 60 grams less as compared Book 1. Which book is heaviest?

If IMPLORE is coded as GKNJMPC, then how will HUB be coded as?

Rampal told Arjun, "Yesterday I defeated the only brother of the daughter of my grandmother." Whom did Rampal defeat?

If S = 19, SUN = 54 and CAKE = 20 , then MISTAKE = ?