钛不仅有强烈的吸气性，而且在高温下与（）有特别的亲和力。
A.氧
B.氮
C.碳
D.二氧化碳
参考答案：C
A fire is discovered in the forepeak of a vessel at sea. The wind is from ahead at 35 knots. You should（）.
A.remain on course and hold speed
B.change course and put the stern to the wind
C.change course to put the wind on either beam and increase speed
D.remain on course but slack the speed
下图表示地球绕日公转的示意图，有可能正确的是（）。
A.①②
B.②④
C.②③
D.①④
