人参药材来源于（）

A.伞形科

B.石竹科

C.豆科

D.毛茛科

E.五加科

Intact buoyancy is a term used to describe（）.

A.the volume of all intact spaces above the waterline

B.an intact space below the surface of a flooded area

C.an intact space which can be flooded without causing a ship to sink

D.the space at which all the vertical upward forces of buoyancy are considered to be concentrated