Which of the two sets are equivalent?

A = {a, c, b} B = {a, b, c}

A = {a, b, c} B = {a, c, d}

A = {1, 2 3, 1, 3} B = {1, 2, 3}

Given the following set S = {a, b, c, d}

Show at least four subsets of S

Show the power set of S.

Please express the following statement using the universal quantification ("for all" quantifier) and the existential quantification ("there exists" quantifier):

Not all numbers are greater than 2.

There exist some numbers which are less than 0