Write the powerset of the following sets
a) {3,7,9}
b) {a,{ 1,2}}
c) {p, q,r, s}
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A. cardinality means no of elements present in the set.
b. no of proper set = 2^n - 1
c. no of subset = n
2^n = 512
2^n = 2^9
n = 9.
Q. power set:
a. { 3,7,9} = {3,7,9,(3 7),(7 9),(9 3)}

The first option would be correct if it were one half and not one