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A 9 feet tall room with a footprint of 12ft×12ft12 mathrm{ft} times 12 mathrm{ft}12ft×12ft is heated by electric resistance radiators on the ceiling, which are maintained at a uniform temperature of 90∘F90^{circ} mathrm{F}90∘F at all times. The floor of the room is 65∘F65^{circ} mathrm{F}65∘F and has an emissivity of 0.8. The sides are well insulated. Treat the ceiling like a black body and determine the rate of heat loss from the room through the floor. A bacterial strain multiplies asexually every 30 minutes. This means that every 30 minutes, each bacterial cell divides into two cells. If there is initially a bacterium, you will find the number of bacterial cells after 1 hour, 2 hours, 3 hours, 4 hours and 5 hours. During _____, minerals such as calcite or quartz crystallize between the grains of clastic rock.