When a car sits at rest, its driver sees raindrops falling on it vertically. When driving the car with speed v, he sees that raindrops are coming at an angle 60∘ from the horizontal. On further increasing the speed of the car to (1+β)v, this angle changes to 45∘. The value of β is close to:
a. 0.50
b. 0.41
c. 0.37
d. 0.73