下列说法正确的是:[ ]
A.扩散现象表明分子永不停息地做无规则运动
B.只有气体之间才能发生扩散
C.固体之间不能发生扩散
D.扩散现象表明分子之间不存在作用力
答案:A
选出错误的选项并改正。
( ) 1. Lynn and I are in a same class. _______________
A B C
( ) 2. Li Ming can say a little English. _______________
( ) 3. The U. K. is west to China. _______________
( ) 4. What colour is these stars? _______________
( ) 5. Look on these beautiful flowers! _______________
燃料气管线的材质是()。
A.L360CS
B.20#
C.A333Gr.6
D.L245