A clock is positioned on an auditorium wall with its center 9 ft above the floor. The second hand on the clock is 10 inches long and continuously moves around the clock. Let x represent the time in seconds measured from noon on a given day.

Which function f(x) represents the height above the floor, in feet, of the tip of the second hand?

f (x) = StartFraction 5 Over 6 EndFraction cosine (StartFraction pi Over 60 EndFraction x) + 9
f (x) = StartFraction 5 Over 6 EndFraction cosine (StartFraction pi Over 30 EndFraction x) + 9
f (x) = StartFraction 5 Over 6 EndFraction cosine (30 pi x) + 9
f (x) = StartFraction 5 Over 6 EndFraction cosine (120 pi x) + 9