更多"Refrigeration machinery is often su"的相关试题:
[单项选择]Diesel engine fuel oil contamination often results in （）
A. governor malfunctions
B. fuel injection system malfunctions
C. high cylinder lube oil temperatures
D. low intake temperatures
[单项选择]Damaged bulkheads often take a permanent set which is independent of the panting or bulge caused by water pressure. To control this，you should（）.
A. install shoring so the shoring supports the damaged bulkheads without pushing on them
B. install shoring so that it pushes on the damaged bulkhead while supporting it
C. use jacks or chain falls to remove the set before installing shores
D. place sandbags by the bulkhead without installing shores
[判断题]Social changes can often bring about language changes.
[单项选择]How often do you（）your brother?
A. hear about
B. hear of
C. hear to
D. hear from
[单项选择]A cloud of marked vertical development (often anvil-shaped) would be classified as（）.
A. cirrus
B. cirrocumulus
C. altocumulus
D. cumulonimbus
[单项选择]Copper is often used as an electrical conductor because it （）.
A. has high resistance at low temperatures
B. has a highly polished surface
C. is able to pass current with little opposition
D. holds insulation together well
[单项选择]When steering by autopilot,how often should the steering be checked?（）
A. 12 times on each watch
B. When time allows
C. At least once a watch
D. No checking is necessary
[单项选择]A fuse that blows often should be replaced only with a fuse of （）.
A. the recommended current and voltage rating
B. higher current and voltage rating
C. higher current and lower voltage rating
D. lower current and higher voltage rating
[单项选择]Mooring winches are often combined with （） units so that one prime mover drives both.
A. crane
B. hatch cover
C. windlass
D. steering gear
[单项选择]A lubricant often has to perform many duties in any situation, in addition to its fundamental job of （）.
A. resisting oxidization
B. reducing friction
C. promoting moving speed
D. developing inertia
[单项选择]A strong，often violent，northerly wind occurring on the Pacific coast of Mexico，particularly during the colder months，is called（）.
A. Tehuan tepecer
B. Papagayo
C. Norther
D. Pampero
[单项选择]How often should the lubricating oil of a diesel engine be changed?（）
A. After every trip
B. Every 4000 hours
C. According to manufacturer’s instructions
D. Every time they are shutdown
[单项选择]It has often been stressed in the Courts that the look-out man should，preferably，be stationed forward，unless weather conditions make this（）.
A. possible
B. practicable
C. impossible
D. probably
[单项选择]The form of cloud often known as mackerel sky which is generally associated with fair weather is（）.
A. nimbostratus
B. stratus
C. cirrocumulus
D. cumulonimbus
