42.何謂應力? (A)負荷施加於材料造成的變形量 (B)材料單位面積所受之負載力 (C)材料的抗力係數 (D)材料的彈力係數

5. If an aircraft is operating at 40,000 ft. the pressurization ensures that (A)sea level pressure is maintained in the cabin. (B)the cabin pressure is progressively increased until the operational height is reached. (C)the cabin pressure above 10,000 ft. (D)the cabin pressure is equivalent to an altitude of less than 10,000 ft.