Consider a thin suspended hotplate that measures 0.4 m × 0.4 m. the isothermal plate has a mass of 3.75 kg, a specific heat of 2770 j/kg·k, and a temperature of 175°c. the ambient air temperature is 25°c and the surroundings temperature is 25°c. if the convection coefficient is 6.4 w/m2·k and the emissivity of the plate is 0.42, determine the time rate of change of the plate temperature, , when the plate temperature is 175°c. evaluate the magnitude of the heat losses by convection and by radiation.