Mohit is standing at some distance from a 60 meters tall building. Mohit is 1.8 meters tall. When Mohit walks towards the building, then the angle of elevation from his head becomes 60° from 45°. How much distance (in metres) Mohit covered towards the building?

A

$$18.6(4 - \surd3)$$

B

$$58.2 - 24.6\surd3$$

C

$$19.4(\surd3+1)$$

D

$$19.4(3 - \surd3)$$