Lombard Street in San Francisco is a switchback road with a speed limit of 8km/hr because if it’s extreme grade. The angle of elevation of Lombard Street in one section reaches 15°. Determine the grade of this section of road.

Question

Please help. I’ve tried drawing out diagram but I am stuck . Thank you!

Answer 1

the grade is the tangent of the angle.
tan15° = 0.2679 or about 27%
pretty steep!

Answer 2

Thank you for your help :)