[High School] Sinusoidal word problems

I have an example of a type of word problem we've been doing. Mainly the things we are asked to do is graph the situation, create an equation, solve for y values, solve for all possible x values.

One type of question involves giving an interval of time, for example how long someone has to get off a Ferris Wheel from a safe height.

I am almost sure for most of these you would need to discover the speed of the wheel/windmill/etc.

I have a specific example that I've had trouble interpreting:

John is stuck on a Ferris Wheel. The wheel has a radius of 10 meters, and it's center is 15 meters off the ground. It rotates 1 time every 60 seconds. The ladder on a firetruck can reach a max height of 7 meters. The truck arrives when John is at the top of the rotation.

It then asks to create an equation, which I have:

let h represent height, t represent time

h = 10cos(6(t))+15

I then figured that I'd need the speed of the ferris wheel:

C=2pi*r

C=2pi*10

C= 62.8319 meters

62.8319 meters/60 seconds = 1.0472meters /second

Here is where I am stuck. I assume the ladder is stuck at a fixed angle, 7 meters off the ground. I know that the wheel's bottom is 5 meters off the ground (middle is 15 meters up, radius is 10 meters). I take this as meaning they only have 1 meter of space to rescue John, because they'd have to be at the tip of the ladder to grab him.

What I guess I have to do is solve for time using the velocity and speed, which gives me 0.95493 seconds, rounded to 2 decimal places (my teacher wants 2 decimal places for final answers, 4 for calculations) it is 0.96.

So is saying they have an interval of 0.96 seconds to rescue John correct, or did I interpret anything wrong?