If A B = {(p, x), (p, y), (q, x), (q, y) }, then A equals which of the following

{ x, y }

{ p, q }

{ p, q, x, y }

None of the above

If A = { 1, 2, 3, 4 } B = { 3, 4, 5 } C = { 5, 7, 8, 9 }

then A C U B equals

		{ 3, 5 }
		{ 3, 4, 5 }
		{ 4, 5 }
		None of the above

If A = { 1, 2, 3, 4 } B = { 3, 4, 5 } C = { 5, 7, 8, 9 }

then A U B C equals

		{ 5 }
		{ 3, 5}
		{ 1, 2, 4, 5 }
		None of the above