a) false (all elements in d does not contain in c)

b) true ( 9x3 = 27)

c) false (27 is not a perfect square)

d) true (3,6,9 is multiple of 3)

e) false

f) true ( 100 is perfect square)

g) true (144 is multiple of 3)

h) true (15 is multiple of 3)

b) true, 9x3 = 27

c) false, 5^2 = 25, 6^2 = 36,√27 = 5.196

d) false, E is a set

e) false

f) true, 10^2 =100

g) true, 144/3 = 48

h) false, 15 is not a proper subset of A