【单选题】The four basic components of a fire are fuel, heat, oxygen and a chain reactionWhich of the following statements best describes what must be eliminated to extinguish a fire?
A.
Any one component can be eliminated to extinguish a fire
B.
Any two components must be eliminated to properly extinguish a fire
C.
Any three components must be eliminated to properly extinguish a fire
D.
Ali four components must be eliminated to extinguish any fire
【简答题】Hybride composites combine two or more different fibers in a common matrix. The four basic types of hybrids are A) ______, B) ______, C) ______, and superhybrids.
【单选题】The contemporary legal systems of the world are generally based on one of four basic systems ( ), common law, statutory law, religious law or combinations of these.