Who discovered free-living cells in pond

Select the option that is related to the third term in the same way as the second the term is related to the first term.

According to the logic used in the first pair, replace the question mark with the appropriate option given to

Cytology : Cells :: Entomology : ??

If 18 & 6 # 32 = 76 and 60 # 6 & 5 = 10, then 15 & 5 # 42=?

"Vanish" is related to "Disappear" in the same way as "Prudent" is related to "____".

Select the option that is related to the third term in the same way as the second term is related to the first term.

72: 81:: 92: ?

Select the option that is related to the third term in the same way as the second term is related to the first term.

Fungi: Mycology :: Insects:?

Select the option that is related to third number-cluster in the same way first number cluster is related to second number-cluster.

HJIK : MONP : : PRQS : ?

‘Greedy’ is related to ‘Generous’ in the same way as ‘Vindictive’ is related to: