A street slopes downward at an angle of 15° with the horizontal. A ball is rolling on the street. How far does
the ball roll when it has covered a horizontal
distance of 120 meters?

It would be 32.15 meters
You can draw a right triangle (Observe the figure attached. It is not drawn to scale), where "x" is the the amount of meters the street rises over a horizontal distance of 120 meters.
You need to use the following Trigonometric Identity:

In this case, you can identify that:

Then, knowing these values, you can substitute them into:

And finally, you must solve for "x" in order to find its value.

The answer for this question is 80