How many permutations of the letters ABCDEFG contain
a) the string BCD?
b) the string CFGA?
c) the strings BA and GF?
d) the strings ABC and DE?
e) the strings ABC and CDE?
f) the strings CBA and BED?
How many permutations of the letters ABCDEFG contain
a) the string BCD?
b) the string CFGA?
c) the strings BA and GF?
d) the strings ABC and DE?
e) the strings ABC and CDE?
f) the strings CBA and BED?