Determine the minimum angle at which a roadbedshould be banked
so that a car traveling at 20.0 m/s can safelynegotiate the curve
if the radius of the curve is 2.0x10 to the 2ndm.

To solve this problem, apply the concepts related to the relationship given between the centripetal Force and the Weight.

The horizontal force component is equivalent to the weight of the car, while the vertical component is linked to the centripetal force exerted on the car, therefore,

Equating both equation we have that,

Rearranging to find the angle we have that,

Our values are given as,

Therefore the minimum angle will be 11.53°

if you already have the answer to (a), then just work out how many periods there are in 1 minute, and that's the answer to (c).

think its the third option