Television and radio stations use four call letters starting with W or K, such as WXYZ or KRLD. Assuming no repetitions in the

Question

Television and radio stations use four call letters starting with W or K, such as WXYZ or KRLD. Assuming no repetitions in the second to fourth letters, how many four-letter sets are possible using either W or K and only the letters C to T? (Count all possibilities even though, practically, some may be inappropriate.) 
There are four-letter sets that can be formed.

Kunduz · Accepted Answer

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