Answer
$y=5sin(4\pi t)$
Work Step by Step
We translate the word problem into math equations: "2 cycles every second" means the
frequency $f=2$, "distance between the highest point and the lowest point" corresponds to twice the oscillating amplitude $2a=10$cm, so $a=5$cm. Use the relationship $\omega=2\pi f=4\pi$, the equation becomes $y=5sin(4\pi t)$
