Given:
Height of ramp = 19.6 m
Final Velocity = 4.9 m/s
The angle slows down the ball by 3.7 m/s
Let's find the initial velocity of the ball.
To find the initial velocity, apply the motion formula:

Where:
v is the final velocity = 4.9 m/s
u is the intial velocity
Since the ball slows by 3.7 m/s each second, the decceleration, a = 3.7 m/s²
s is the height = 19.6 m
Rewrite the formula for v and input values into the formula:

Take the square root of both sides:
![\begin{gathered} \sqrt[]{u}^2=\sqrt[]{169.05} \\ \\ u=13.0\text{ m/s} \end{gathered}](https://img.qammunity.org/2023/formulas/physics/college/7l2ewk7pkuqibfudcc0dsezdq6n3vwdccc.png)
Therefore, the initial velocity of the ball is 13.0 m/s.
ANSWER:
13.0 m/s