船轴不包括（）。
A.推力轴
B.中间轴
C.艉轴
D.曲轴
参考答案：D
一元二次方程2x2-6=0的二次项系数为______，一次项系数为______．
In relation to the law of contract, explain each of the following:
(a) unliquidated and liquidated damages; (4 marks)
