During series conduction of multiple materials, what can be said about their thermal conductivities? a. It depends on the material. b. All thermal conductivities must be taken from the average of the outside and inside temperature. c. All thermal conductivities must be greater than one. . d. More than one response. . None of these. In transition region, the layers of fluid start to form a disturbance. What can be concluded about the hydrodynamic boundary layer? This layer is more disturbed than the free stream. b. This layer is less disturbed than the free stream. The disturbance at the free stream is the same as that of the boundary layer. . . d. More than one response. . None of these. If Re = 2152.0221, what must be the value of Pr so that Pe = 45.28? Pr = 97443.5607 . b. Pr = 0.2104 . Pr = 47.5270 d. More than one response. . None of these.