Steam smoke will occur when（）.

Spring tides occur______．

A.when the moon is new or full

B.when the moon and sun have declination of the same name

C.only when the moon and sun are on the same sides of the earth

D.at the beginning of spring when the sun is over the equator

When using a hand held smoke signal from a lifeboat, you should activate the signal _____.

A.on the downwind side

B.on the upwind side

C.inside the boat

D.at the stern

A.When compile, some error will occur.

B.When run, some error will occur.

C.Output is zero.

D.Output is null.

Steam smoke will occur when ______.

A.extremely cold air from shore passes over warmer water

B.warm dry air from shore passes over cooler water

C.cold ocean water evaporates into warm air

D.cool rain passes through a warm air mass

The engine______smoke and steam．

A.gives up

B.gives away

C.gives in

D.gives off

Water, when boiled, always ______ steam.

A. gives in

B. gives up

C. gives off

D. gives away

Neap tides occur ______.

A.at the start of spring, when the Sun is nearly over the equator

B.only when the Sun and Moon are on the same sides of the Earth and are nearly in line

C.when the Sun and Moon are at approximately 90°to each other, as seen from the Earth

D.when the Sun , Moon, and Earth are nearly in line, regardless of alignment order

Which statement is TRUE concerning equatorial tides ________．

A.They occur when the Sun is at minimum declination north or south

B.They occur when the Moon is at maximum declination north or south

C.The difference in height between consecutive high or low tides is at a minimum

D.They are used as the basis for the vulgar establishment of the port