观察下边漫画,图中蜈蚣寓意着
A.德国
B.俄国
C.日本
D.美国
答案:C
(2分)下列物质属于纯净物的是( )
A.铁锈
B.小苏打
C.汽水
D.石油
Green water near coastlines is almost always caused by ______.
A.sand color
B.red pigments in coastal waters
C.blue pigment
D.reflected light and yellow pigment from plant life