I need help with these. I'm so confused! Thanks!

Question

1.) An F-14 Tomcat fighter jet goes from rest to a speed of 75m/s in 2.5 s. What is the acceleration?

2.) Preston tossed a red ball upward and it reaches a maximum height of 3.0m What is the final velocity when it returns to Preston's hand?

Answer 1

acceleration = change in velocity / change in time

same as speed on the way up, but down not up or in other words it falls from 3 meters up

m g h = (1/2) m v^2
so
v = -sqrt(2 g h) = -sqrt ( 2 * 9.81 * 3)