The direction of the jet of coolant lubricant is __________.
A: fixed and can be closed
B: fixed and can’t be closed
C: adjustable and can be closed
D: adjustable and can’t be closed
A: fixed and can be closed
B: fixed and can’t be closed
C: adjustable and can be closed
D: adjustable and can’t be closed
举一反三
- you can see a shop closed down because they can’t ______ it.
- He can on the bed with his ____. A: closed eyes and his mouth open B: eyes closed and his open mouth C: closed eyes and open his mouth D: eyes closed and his mouth open
- Few words can be added to closed class words。 （ ）
- A control volume is: （ ） A: An isolated system B: A closed system but heat and work can cross the boundary C: A specific amount of mass in space D: A fixed region in space where mass, heat and work can cross the boundary of that region
- The curl equation [img=154x44]1803a2a153c85f5.png[/img]shows that : A: The time-varying magnetic field can generate an electric field, in which the elecric field lines is closed around the magnetic field line. B: The time-varying magnetic field can generate a magneitc field, in which the magnetic field lines is closed around the electric field line. C: The magnetic field lines is closed themselves. D: Flux continuity