The is a measurement unit for intensity of sound. a) meter b) decibel c) degree

decibel

It is the unit of sound abbreviated as dB. It is also defined as Power per square meter, Therefore intensity of sound expressed in Watt per square meter (W/m2).

Decibel (dB)is the unit of expressing the ratio between two physical quantities, usually amounts of acoustics or electric power or measuring the relative loudness of sounds.

the moving of the box is a result of centripetal force. think of that  as a car or a truck in this case creates a turn, the force of friction performing upon the turned wheels of the car runs centripetal force obligatory for circular motion for the things inside it.