Answer:
The 20.6 m/s will be the speed of ball after 3 seconds.
Step-by-step explanation:
Initial velocity of the ball = u = 50 m/s
Final velocity of the ball = v = ?
Acceleration due to gravity = a =
![-9.8m/s^2](https://img.qammunity.org/2020/formulas/physics/middle-school/w2l3wewmih9454o401wbcqp04sk2ogm7h0.png)
( ball is thrown against the gravity)
(first equation of motion)
![v=50 m/s-9.8 m/s* 3s](https://img.qammunity.org/2020/formulas/geography/college/d0pwi4naikrkv7iohngwduazv9s9rpg058.png)
![v = 20.6 m/s](https://img.qammunity.org/2020/formulas/geography/college/7uc0v7mwhiih2pjfmm0kg6j08yoneyco4o.png)