Answer:
1.Velocity and pitch
2.The unit of vibration is hertz. The number of oscillations of an oscillating body per second is known as frequency. Complete step by step answer: The time taken by a vibrating body to complete one vibration is time period.
3.Frequencies above 20,000 Hz are known as ultrasound.
Just search up how much the weight is equal to another, then multiply it, thats what i do lol sorry if im no help
Option 1/A (It is the first one)
You know that you can just google it right? It has this converter.