1. A ball is dropped off of the roof of a building. We can measure the height of the ball of the ground in meters t seconds after the ball is released by the function s(t) = -10t^2 + 160.

a. what is the height of the roof of the building? (Hint: Think about what time the ball is on the roof of the building)

b. At what time does the ball hit the ground?

c. what is the ball's velocity when it hits the ground?

d. what is the ball's acceleration when it is initially released?

2. For x^2 +y^2 +2x =7, find y' (the implicit derivative), and find the equation of the tangent line at (1,2)