Select the correct answer.
given
d = {x | x is a whole number}
e = {x | x is a perfect square between 49 and 100}
f = {x | x is an even number between 10 and 20}
the expression d ∪ f means (all whole numbers, 64 and 81).
the expression d ∩ f means (16 22 24 18, 12 14 16 18).
the expression d ∩ e means (64 81, all whole numbers).
the expression e ∩ f means (the empty set, all whole numbers).
the expression d ∩ (e ∪ f) means (empty set, 81 64 12 14 16 18).