Answer:
a) Initial velocity of the ball=14.5 m/s
b)The ball rise to a height of 10.72 m/s
c)The velocity of the ball is zero at the highest point.
Step-by-step explanation:
Taking point at which the ball is thrown to be origin. Distanced measured to be positive in upwards directions.
a)
Now using equation of motion

The initial velocity of the ball is

b) Let h be the height that ball rise above the starting point given by

c)The ball will be at rest with zero velocity at the highest point