Question

Consider the sets.
A = {distinct letters in the word keep}
B = {13}
C = {k, e, p}
D = {6 + 1}
E = {seven}
F = {7}

(a) What is the cardinality of each set?

Answer 1

I know the cardinality for b=1
c=3
d=1
e=1
f=1
just don't know for letter A?
also want to confirm that is right..

Answer 2

I don't know