The price of a technology stock has dropped to $9.60 today. Yesterday's price was $9.67. Find the percentage decrease. Round your answer to the nearest tenth of a percent. Please help. please get it right I am trying to get done with math. :)

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.

The tile along the edge of a triangular community pool needs to be replaced? ?

Proportions in triangles solve for x