Question

During a 12- hour period, the tides in one area of the Bay of Fundy causes the water level to rise to 6 m above the average sea level and to fall 6 m below average sea level. The depth of the water at low tide is 2m as measured against a pier.

Suppose the water is at average sea level (rest position) at 0:00 hours (midnight) and the tide is coming in. Draw a graph that shows the height of the tide over a 24-hours period. Explain how you obtain the graph???

I really appreciate any help.