The Reynolds number at the point (adopting 5 as the relevant constant) is

Question

The thickness of the boundary layer for a fluid flowing over a flat plate at a point 20 cm from the leading edge is found to be 4 mm.  The Reynolds number at the point (adopting 5 as the relevant constant) is

         (a)  48400              (b) 57600

         (c)  62500             (d) 77600