Let U = {q, r,s, t,u, v,w, x,y, z}, A={q, s,u, w,y}, B={q, s,y, z}, and C={v, w,x, y,z}. List the elements in the set open parentheses A union B close parentheses to the power of apostrophe intersection C

If m∠abc = 70°, what is m∠abd? justify your reasoning.  using the addition property of equality, 40 + 70 = 110, so m∠abd = 110°.  using the subtraction property of equality, 70 − 30 = 40, so m∠abd = 30°.  using the angle addition postulate, 40 + m∠abd = 70. so, m∠abd = 30° using the subtraction property of equality.  using the angle addition postulate, 40 + 70 = m∠abd. so, m∠abd = 110° using the addition property of equality.