1. What is the difference between a crest and a trough of a wave?

3. What is the wavelength of a wave?

4. Wavelength
the distance from a particular height on the wave to the next spot on the wave where it is at the same height and going in the same direction

5. How are frequency and period related to eachother?

6. Frequency (f) and period (T) are exact inverses of each other
there is a very basic pair of formulas you can use to calculate one if you know the other

7. What is the amplitude of a wave?

8. the height from the equilibrium point to the highest point of a crest
the height from the equilibrium point to the highest point of a crest or
the depth from the equilibrium point to the lowest point of a trough

9. What math will we have to do this unit?
V = f l
V = velocity
F = frequency
l= wavelength