1. [单选题]某船真航向060°，该船右正横某物标的真方位为：()
A. 150°
B. 330°
C. 090°
D. 060°
2. [单选题]零件疲劳断口的最后断裂面积较小，小于断口面积之半时，表明零件( )。
A. 过载
B. 不过载
C. 材料强度低
D. 材料强度高
3. [单选题](piston area)×(piston stroke)×(numbers of the cylinders)=engine( ).
A. brake horsepower
B. displacement
C. cylinder volume
D. cylinder clearance
4. [单选题]我国《海船船员发证规则》规定，持有海船船员适任证书者，应在其适任证书有效期的最后______个月内，向海事管理机构申请适任证书再有效，以换领新的适任证书。
A. 3
B. 6
C. 9
D. 12
5. [单选题]_______can cause oil flow from water outlet of the oil purifier.
A. Oil inlet valve opening too quickly
B. Oil temperature little higher than normal
C. Diameter of gravity disc too small
D. Viscosity of oil little lower than normal
