That means, figure out how many different subsets a set has. In general, if a set has n elements, it has 2n different subsets.
If you have a set of 6 elements, you can make a total of 26 different subsets - including the empty set and the set itself.
If the set has "n" elements, then you can make 2n different subsets. The number of subsets will always be greater than the size of the set, both for finite and for infinite sets.
No. The number of subsets of that set is strictly greater than the cardinality of that set, by Cantor's theorem. Moreover, it's consistent with ZFC that there are two sets which have different cardinality, yet have the same number of subsets.
8 subsets
An element doesn't have subsets. Sets can have subsets.
Two. The set {x} has the subsets {} and {x}.
The number of elements. A set with n elements has 2n subsets; for example, a set with 5 elements has 25 = 32 subsets.
A finite set with N distinct elements has 2N subsets.
A set with N elements has 2N subsets.
If the set has n elements, the number of subsets (the power set) has 2n members.
Elements belong to subsets: subsets contain elements (from the parent set).