Which of the following statements is untrue in regard to sound traveling in air? a. as the distance from the earth increases, the sound wave intensity also decreases due to the lessening density. b. the area covered by the wave front increases as the wave advances, but the energy passing through a wave front in a unit of time decreases. c. during a single vibration of the diaphragm, molecules in the air near it will also complete one vibration. d. sound waves in the air are transverse and consist of compressions and rarefactions of air molecules.

Awater balloon launcher uses an elastic band with a spring constant of 115 n/m to use thee launcher you stretch thee band back with a balloon n it the water balloons have a mass of 1.3 kg a) if you stretch the band by 0.8 m, what elastic force will the band exert? b) with the band stretched 0.8 m, how much elastic potential energy is stored in the spring? c) if you release the band, it pushes forward. what is the kinetic energy of the balloon when it reaches the natural length of the band? d) what is the speed of the balloon when it reaches the natural length of the band?