If you blow up a balloon, then put it in a room with a lower pressure, what should happen to the volume of the balloon

Volume increases

Explanation:

According to Boyle's law, the pressure will increase with the decrease in volume or pressure will decrease with the increase in volume.

If a balloon kept in a room with a lower pressure then its volume will increase because the pressure is directly proportional to the number of gas molecules in the balloon, lower pressure means less collision of air molecules, and more volume will be occupied by the air molecules.

Hence, the volume will increase by lowering the pressure.

diagram is missing, but i will try to explain your doubt.

answer:

amplitude is the maximum displacement or distance moved on a point of a vibrating body or wave measured from its equilibrium position.it is equal to half the length of vibration path.