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We can use the conservation of angular momentum to solve.

I = moment of inertia (kgm²)
ω = angular velocity (rad/sec)
Recall the following equations for the moment of inertia.

Begin by converting rev/sec to rad sec:

According to the above and the given information, we can write an equation and solve for ωf.

Compound and events are pure substance
Given that,
Angle = 30°
Initial velocity = 15 m/s
We need to calculate the time of flight
Using formula of time of flight

Where, u = initial velocity
g = acceleration due to gravity
Put the value into the formula


We need to calculate the final velocity of the ball
Using equation of motion



Hence, The final velocity of the ball is 29.7 m/s.
False, it does create pollution form the smoke stacks and after the process is done they have barrels of toxic waste