College math
posted by Shin .
Highwq curves. If a circular curve without any banking has a radius of R feet, the speed limit L in miles per hour is L = 1.5 aqrt(R)
(a) Find the speed limit for a curve having a radius of 400 feet.
(b). If the radius of a curve doubles, what happens to the speed limit?
(c.) A curve with a 40mileperhour speed limit is being designed .What should be its radius?

What is your thinking? I will be happy to critique your thinking.