Answer:
I think the answer is True
An opera singer breaks a thin glass with only the use of her high frequency voice
So the initial velocity is 15 m/s, the final velocity is 0 since it's at a complete stop and time is 10 seconds. Therefore:

Therefore, the acceleration is -1.5 m/s^2. The reason it's negative is due to the fact that the vector is going against it's original movement since it's decelerating.
Acceleration of an object is depended upon the net force acting open the object and the mass of the object