The answer would be D hope it helps and sorry if it is wrong. :)
B: CaO
Because Calcium is a Metal and Oxygen is a Non-Metal. Ionic bonds are only formed with a Metal and a Non-Metal element.
We need to consider no change in the temperature of gas (isothermal transformation)
Volume and pressure are inversely proportional magnitudes, so we can write:
Answer: Vibrating
Explanation:
Sound is produced when an object vibrates. The sound vibrations cause waves of pressure that travel through a medium, such as air, water, wood or metal. Sound is a form of mechanical energy.