班轮货物运输的主要特点包括（）。
A．固定航线
B．固定装卸港
C．固定船期
D．固定运价
参考答案：A,B,C,D
曲线。（0≤x≤π）与x轴围成的平面图形绕x轴旋转一周而成的旋转体体积等于（）。
A.A
B.B
C.C
D.D
A client with chronic obstructive pulmonary disease (COPD) and cor pulmonale is being prepared for discharge. The nurse should provide which instructions（）
A. "Weigh yourself daily and report a loss of 1 lb in 1 day. "
B. "Eat a high-sodium diet. "
C. "Weigh yourself daily and report a gain of 2 lb in 1 day. "
D. "Maintain bedrest. "
。（0≤x≤π）与x轴围成的平面图形绕x轴旋转一周而成的旋转体体积等于（）。