In each of the following questions, two numbers are given which follow a certain logical or arithmetic relationship. Identify the same pattern and apply it to find the missing number in the second pair. Choose the correct option from the given alternatives.
40321: 62543 :: 56120 : ?

Select the option that is related to the first letter cluster in the same way as the fourth letter cluster is related to the third letter cluster and sixth letter cluster is related to fifth letter cluster.
SEP : ? :: WKJ : BPO :: IQV : NVA

4 is related to 10 following a certain logic. Following the same logic, 34 is related to 40.  To which of the following is 66 related, following the same logic?
(NOTE: Operations should be performed on the whole numbers, without breaking down the numbers into their constituent digits. E.g. 13 – Operations on 13 such as adding/subtracting/multiplying to 13 can be performed. Breaking down 13 into 1 and 3 and then performing mathematical operations on 1 and 3 is not allowed.)

Select the set in which the numbers are related in the same way as are the numbers of the following sets.
(NOTE: Operations should be performed on the whole numbers, without breaking down the numbers into their constituent digits. E.g. 13 – Operations on 13 such as adding/subtracting/multiplying to 13 can be performed. Breaking down 13 into 1 and 3 and then performing mathematical operations on 1 and 3 is not allowed.)
(37, 48, 59)
(41, 52, 63)​