40. 凡經由法定時間測試，其背火一面的平均溫升不超過140℃，而且任何位置之溫度不超過原溫度180℃，此乃認可的耐燃材料。若材料為A-60級數，則表示之意義為何？ (A) 於60秒內，符合上述測試條件 (B) 於60分鐘內，符合上述測試條件 (C) 於120秒內，符合上述測試條件 (D) 於120分鐘內，符合上述測試條件

39. Check valves must be provided on pump suctions to prevent pumping through the standby pump to the sump. Pump isolating valves should be provided to permit underway repair of either pump. Based on these descriptions, which is the correct statement？ (A) The isolating valves must be non-return valves. (B) The check valve also needs to be positioned at the pump exit in order to improve the pumping efficiency. (C) The check valve allocated on pump suctions permits no flow from the idle pump into the sump. (D) The check valve allocated on pump suctions permits the isolation of the running and standby pumps so that the isolating valves could be ignored for the emergency operation.

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