Estimate how long will it will take to cool a trailer filled with coke. given the ambient temperature is 20 °c and heat transfer provided by the refrigeration unit is 25kw and the drinkable temperature is 5 °c. make reasonable estimates of how much insulation is included on the walls of the truck. assume the coke cans are stacked in rows inside the truck with sufficient space for air to circulate between them. assume an air flow velocity inside the truck of 0.35 m/s. assume the sun is incident on the external surface of the truck for part of the time. indicate any assumptions you make in your analysis. take the properties of coke as: specific heat capacity 4000 j/kgk, density 1000 kg/m3 and thermal conductivity of 0.5 w/mk