Use the formula h = −16t² + v₀t. (If an answer does not exist, enter DNE.)

A ball is thrown straight upward at an initial speed of v₀ = 72 ft/s.

(a) When does the ball initially reach a height of 80 ft? _____s

(b) When does it reach a height of 103 ft? ______s

(c) What is the greatest height reached by the ball? ____ft

(d) When does the ball reach the highest point of its path? _____s

(e) When does the ball hit the ground? _____s