A nail is stuck in a car's tire. The position of the nail with respect to the ground (in inches) is represented by the function $y = - 18\cos{\left( 2x \right) +}18$, with time in $x$ seconds. When does the nail reach a height of 34 inches on the interval $0 < x < 4$?

The position of a rung on a waterwheel in feet above water level is represented by the function $y = - 18\sin{\left( \frac{\pi}{6}x \right) +}12$, with time in $x$ seconds on the interval $0 < x < 10$. When is the rung 4 feet under water?

The depth of ocean waves in feet can be represented by the function $y = - 4\cos{\left( \frac{\pi}{12}\left( x - 3 \right) \right) +}8$, with time in $x$ hours on the interval $0 < x < 24$. When are the waves 10 feet high?

The height of ocean tides can be represented by the function $y = 10\sin{\left( \frac{\pi}{8}(x - 4) \right) +}16$, with time in $x$ hours. Graph the function using a graphing utility on the interval $0 < x < 24$. When is the tide 20 feet high?