Remember that for a graphic of a trigonometric functions of the form
![f(x)=Acos(Bx+C)+D](https://img.qammunity.org/2019/formulas/mathematics/high-school/v1dyl79nrov0d466x2c2ng84d5gqjcraba.png)
![A](https://img.qammunity.org/2019/formulas/mathematics/college/k9eyhyc0oq8synfrd8d989siquy6r5rpla.png)
is the amplitude of the function
![f(x)=D](https://img.qammunity.org/2019/formulas/mathematics/high-school/p5u54jmwf2ryqhkmtltq7b7hozmz81kdxx.png)
is the midline of the trigonometric function
We know form our problem that
![A=5](https://img.qammunity.org/2019/formulas/mathematics/high-school/dztmxpj1mh9udkcxqcgbsag5cdu3921wez.png)
, so the amplitude of our function is 5. We also know that the
![D=7](https://img.qammunity.org/2019/formulas/mathematics/high-school/a2abwg97kp4ma1cfyki81vxs03lvlsbq78.png)
. So the midline of our function is the line
![h(t)=7](https://img.qammunity.org/2019/formulas/mathematics/high-school/fpd70hqdc64iu7g05rppizey3gfokhultf.png)
.
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: