Answer
a. Yes.
b. 1
c. 2
d. Yes.
e. No.
Work Step by Step
a. Two is an element of the set containing two.
b. The number of unique elements in the set is one.
c. Because 0 and {0} are not the same thing (a number versus a set containing a number), there are two distinct elements in the set.
d. The set {0} is an element of the set containing the sets {0} and {1}.
e. 0 is an element of {0}, but 0 is not an element of {{0}, {1}}.
