Question

The height, h, in feet of a piece of cloth tied to a waterwheel in relation to sea level as a function of time, t, in seconds can be modeled by the equation h=15cos(3.14/20 t). How long does it...

Answer 1

 0.1    t  =  2
 t  =  20 seconds.
is that what you're asking?

Answer 2

Answer: On edg it’s D: 40 seconds

Just did it