【单选题】Which of the following statements is correct concerning the viscosity of lubricating oil?
A.
Viscosity will increase as temperature increases
B.
Viscosity is a measure of a fluid s internal resistance to flow
C.
Viscosity will decrease as temperature decreases
D.
Viscosity is not dependent on temperature
【单选题】下列关于债券与股票的说法中,错误的是( )。
C.
债券通常有规定的票面利率,而股票的股息红利不固定
【简答题】30×13= 33×10= 540÷9= 280÷4= 600÷3= 50×80= 460÷2= 30×70= 300÷6=
【单选题】The amount of fluid friction or internal friction inherent in a mineral lubricating oil is reflected as a measure of its _____.
【单选题】Which lubricating oil additive is used in diesel engines to reduce the tendency(倾向)for sludge and varnish to form on the engine parts?