Respuesta :
Answer:
the speed after 2 seconds = 20m/s
Explanation:
I took g as -10m/s² because the ball was moving against gravity
using V = u + gt
V = 40 - 10 X 2
V = 40 - 20
V = 20m/s
I got the same answer: after 2 second the speed of the ball will be 20 m/s