For A = {1, 2, 3, 4, 5, 6, 7}, determine the number of (a) Subsets of

Question:

For A = {1, 2, 3, 4, 5, 6, 7}, determine the number of
(a) Subsets of A
(b) Nonempty subsets of A
(c) Proper subsets of A
(d) Nonempty proper subsets of A
(e) Subsets of A containing three elements
(f) Subsets of A containing 1, 2
(g) Subsets of A containing five elements, including 1, 2
(h) Subsets of A with an even number of elements
(i) Subsets of A with an odd number of elements