Final answer:
The model for the height of a rope as a function of time is h(t) = 39sin(2πt) + 39.
Step-by-step explanation:
The model for the height h (in inches) of a rope as a function of time t (in seconds) is given by option a) h(t) = 39sin(2πt) + 39.
This equation represents a sinusoidal function, where the amplitude of the wave is 39 inches and the period of the wave is 1 second. The sine function oscillates between -1 and 1, so adding 39 to the function raises the lowest point of the rope to 39 inches above the ground.