Need help with parts b, c, and d

Problem 14: (7% of Assignment Value) One ball is dropped from rest from a height of 58 m. At the same time, another ball is thrown upward from the ground with initial velocity of 33 m/s. It takes time At for them to be side by side at some height h2 above the ground. The +y-direction is upward. Otheexpertta.com Part (a) v What is the acceleration of the two balls, a, in meters per second squared? a = -9.8 a=-9.800 m/s2 Correct! Part (b) Express the displacement of the ball falling down, Ay, when the two balls meet in terms of At and the acceleration found in part (a). Ayl = 0.5 ( -9.8 ) (At )2 X Attempts Remain Feedback: Use an appropriate symbol to represent the acceleration rather than the numerical value of 9.8 m/s Part (c) Express the displacement of the ball going upward, Ay2, when the two balls meet in terms of its initial velocity U2, At, and the acceleration found in part (a). Ay2 = 33 At + 0.5 ( - g ) (At )2 X Attempts Remain Part (d) Express the height h in terms of Ay and Ay2. h = Ay1 - Ay2 X Attempts Remain Feedback: . It appears that there may be a sign error associated with at least one term in your expression