Verbal Reasoning - Mental Ability Questions

Which set of letters when sequentially placed at the gaps in the given letter series shall complete it?

_r_r_t_r_r_t

In the following question, select the related number from the given alternatives.
9143 : 9963 : : 6731 : ?

If 8 θ 12 δ 6 = 60 and 13 θ 15 δ 11 = 74, then 18 θ 21 δ 15 = ?

If 23 x 16 = 184, 37 x 10 = 185, then 85 x 12 = ?

Select the related word/letters/number from the given alternatives.
66 : 36 : : 99 : ?

In a code language, BURN is written as YFIM. What is the code for WOUND?

Findout the odd word/letters/number/number pair from the given alternatives.

If 4 cats can kill 4 rats in 4 minutes, how many minutes will it take 8 cats to kill 8 rats?