In the questions below determine the size (i.e. cardinality)

Question

of the set.
• {x|x ∈ N, x2 < 10}
• P({a,b,c,d,e }) where P denotes the Power set
• A × B where A = {1, 2, 3, 4, 5} and B = {1, 2, 3}
• {x|x ∈ Z, 9x2 −1 = 0}
• A × B where A = {a, b, c} and B = ∅