Analogy Questions

Choose the related word/letters/number from the given alternatives. 19 : 6859 : : 21 : ?

Select the related word/letters/number from the given alternatives.
AEG: GKM :: MQS : ?

In the following question, select the related word pair from the given alternatives.
Heart : Organ : : ? : ?

In the following question, select the related number from the given alternatives.
243 : 578 : : 163 : ?

Select the related number from the given alternatives.
12.5 : 6.25 :: 7 : ?

In the following question, select the related number from the given alternatives.
4 : 17 : : 7 : ?

In the following question, select the related number from the given alternatives.
5 : 130 : : 6 : ?

Select the related word/letters/number from the given alternatives.
Luminous intensity : Candela : : Pressure : ?