1. [单选题]热敷有助于(helpful to)______。
A. 促进血液循环
B. 加速炎症吸收
C. 减轻疼痛
D. 以上都对
2. [单选题]A crack in a cylinder liner can be caused by
A. worn piston rings
B. installation of undersized sealing rings
C. operating the engine at low loads
D. restricted cooling water passages
3. [单选题]Ⅰ航区的货船，全船配备的救生艇、筏乘员占总人数：
A. 150%
B. 200%
C. 250%
D. 100%
4. [单选题]保留在船上的样品需要根据()进行保存。
A. 相似性
B. 相容性
C. 毒性
5. [单选题]By comparing the exhaust gas temperature of each cylinder, the operator can determine if the load is balanced throughout the engine The device most commonly used is a
A. tachometer
B. pyrometer
C. dynamometer
D. calorimeter
