How many subsets does the empty set {} have?
0
No. Remember, every subset is a subset of itself.
1
Correct! The only subsets of the empty set are the empty set.
2
No. Think about what the subsets would be.
4
No. Think about what the subsets would be.
What should subsets
report in the base case?
A list containing a list with each item of the set.
No. How many subsets does the empty set have? Remember, every set is the subset of itself.
A list containing a list with the first item of the set.
No. How many subsets does the empty set have? Remember, every set is the subset of itself.
A list containing an empty list.
Correct!
A list containing a list with randomly chosen items from the set.
No. How many subsets does the empty set have? Remember, every set is the subset of itself.
How many subsets of {Apple, Orange, Banana} contain Apple?
1
No. Both {Apple, Banana} and {Apple} are subsets of {Apple, Orange, Banana}, so there is
clearly more than one subset containing Apple.
4
Correct! - [Apple] [Apple, Orange] [Apple, Banana] [Apple, Orange, Banana]
6
No. Think about the individual subsets that would contain Apple.
8
No. Could all subsets contain Apple?