A barbeque grill is built from bricks which act as insulating surfaces, and it is large enough (about 2 feet in diameter) to be able to cook 25 or more hamburgers simultaneously. The rack on which the charcoal is placed is fixed on the grill, and the rack on which the burgers are placed is adjustable in height increments of 7 cm, starting at a minimum of 10 cm. When the grill is initially set up for cooking, the charcoal rack is completely covered with briquettes 2 cm in diameter. The bri- quettes are very black, and they reach a temperature of 700°C after being ignited. After the charcoal reaches its highest temperature, the hamburgers are positioned on the grill as they are removed from the refrigerator at 4 C, and their absorption coefficient can be assumed to be 0.8. The objective of this problem is to compare the performance of the grill with the meat rack placed at the closest and the third to closest settings. Assume that the rack itself does not participate in or affect the heat transfer process. Analyze the process for one 10 cm diameter hamburger placed in the middle of the grill. What is the initial rate of heat transfer to the surface of the hamburger for the two grill settings?