Throughout the day, the depth of water at the end of a dock varies with the tides. the function h(t)=5cos(0.5t-2)+7 represents the height, in feet, of the water t hours after midnight. which graph shows the height of the water at the dock at any time after midnight?

Remember that for a graphic of a trigonometric functions of the form 
is the amplitude of the function 
is the midline of the trigonometric function 

We know form our problem that , so the amplitude of our function is 5. We also know that the . So the midline of our function is the line . 

Using those two features we can conclude that the graph that shows the height of the water at the dock at any time after midnight is: