How many permutations of the letters ABCDEFG contain:

I will treat blocks of letters as a single object in the permutation

a) the string BCD?
5! = 120
b) the string CFGA?
4! = 24
c) the string BA and GF?
5! = 120
d) the string ABC and DE?
4! = 24
e) the string ABC and CDE?
The string blocks overlap but it is possible to make it a single block
3! = 6
f) the string CBA and BED?
The string blocks overlap but we can't make it a singly block
0 It can't exist!