單項選擇題

A sign of thunderstorm development is a cumulus cloud（）.

A.darkening，growing in size and forming an anvil top
B.that shows extensive vertical development
C.creating cold downdrafts that are felt on the ground
D.All of the above

你可能感興趣的試題

單項選擇題

A shipmate suffers a heart attack and stops breathing. You must（）.

A.administer oxygen
B.immediately check his pulse and start CPR
C.make the victim comfortable in a bunk
D.immediately give a stimulant，by force if necessary

單項選擇題

A ship having continuous closely spaced transverse strength members is（）.

A.longitudinally framed
B.transversely framed
C.cellular framed
D.web framed