單項選擇題

Fog forms when the air（）.

A.is 50% water saturated
B.is 90% water saturated
C.temperature is greater than the dew point temperature
D.temperature is equal to，or below the dew point temperature

你可能感興趣的試題

單項選擇題

Five or more short blasts on a vessel’s whistle indicates that she is（）.

A.in doubt that another vessel is taking sufficient action to avoid a collision
B.altering course to starboard
C.altering course to port
D.the stand-on vessel and will maintain course and speed

單項選擇題

After a vessel transmits the original distress message，what signal should be sent to allow ships to take RDF bearings?（）

A.SOS three times
B.Additional transmissions to aid direction finding
C.E for one minute，followed by T for one minute
D.Two tones，10-15 seconds each

<abbr id="lbnwk"></abbr>