The radius of a horizontal circular curve on a highway is $120$ m. The design speed is $60$ km/hour, and the design coefficient of lateral friction between the tyre and road surface is $0.15$. The estimated value of superrelevation required (if full lateral friction is assumed to develop), and the value of coefficient of friction needed (if no superrelevation is provided) will, respectively, be
- $\dfrac{1}{11.6} \text{ and } 0.10 \\$
- $\dfrac{1}{10.5} \text{ and } 0.37 \\$
- $\dfrac{1}{11.6} \text{ and } 0.24 \\$
- $\dfrac{1}{12.9} \text{ and } 0.24$