Question $3.10$ Points

a$)$ What is the time required for One complete vibration of an ultrasonic stethoscope that operates at a frequency of $2\mathrm{.}0MHz(2\mathrm{.}0{10}^6(Hz))?$

b$)$ What is the frequency of a sound wave made by a tuning fork that requires $2\mathrm{.}44{10}^{-4}$ seconds for one complete vibration?

c$)$ Calculate the speed of propagation of an ocean wave if its crests $($peaks$)$ are $20\mathrm{.}0$ meters apart and each crest take $8\mathrm{.}0$ seconds to make one trip up and down.