In a two dimensional incompressible steady flow around an airfoil, the stream lines are 2 cm apart at a great distance from the airfoil, where the velocity is 30 m/sec. The velocity near the airfoil, where the stream lines are 1.5 cm apart, is_________________?
A. 22.5 m/sec
B. 33 m/sec
C. 40 m/sec
D. 90 m/sec