This table gives information about how far hiker walks during the times indicated. Use the data to answer the question. What was the hiker’s average speed for the entire hike?
A.) 2.0 km/h
B.) 6.7 km/h
C.) 5.7 km/h
D.) 10 km/h

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.