Which statement represents a true, reversible statement? a. if it is raining, then the sky is cloudy. b. a quadrilateral with equal sides and equal angles is a square. c. if sarah goes to the dance, then i will go to the dance. d. a dog will have a tail if and only if it is a collie.

What is the next step in the given proof? choose the most logical approach. a. statement: m 1 + m 2 + 2(m 3) = 180° reason: angle addition b. statement: m 1 + m 3 = m 2 + m 3 reason: transitive property of equality c. statement: m 1 = m 2 reason: subtraction property of equality d. statement: m 1 + m 2 = m 2 + m 3 reason: substitution property of equality e. statement: 2(m 1) = m 2 + m 3 reason: substitution property of equality