The local convective heat transfer (in w/m2K) at that location will be

Question

A coolant fluid at 30⁰C flows over a heated flat plate maintained at a constant temperature of 100⁰C. The boundary layer temp distribution at a given location on the plate may be approximated as T = 30 + 70exp(-y), where y (in m) is the distance normal to the plate and T is in ⁰C. If thermal conductivity of the fluid is 1.0W/mk, the local convective heat transfer (in w/m²K) at that location will be     

      (a) 0.2                               (b) 1                             (c) 5                                (d) 10