国家对可用作原料固体废物的国外供货商实行()。
A.供货许可制度
B.备案登记制度
C.注册登记制度
D.资质核准制度
参考答案:C
—Tom has been fired by his boss.
—________?As far as I know,he is a hardworking and considerate fellow.
A.Why not
B.How come
C.What then
D.So what
下列实例中属于机械能转化为内能的是 [ ]
A.内燃机的活塞在燃气推动下运动
B.点燃的火箭飞向太空
C.夏天,广场上的石凳被晒得发烫
D.陨石坠入地球大气层成为流星