—__do you want to go to a movie?
—Let's go at 6:00.[ ]
A. Where
B. When
C. Why
D. How
答案:B
硝酸易发生4HNO3 光照 . 2H2O+4X↑+O2↑反应.
(1)硝酸应放在棕色试剂瓶中,原因是______;
(2)X的化学式是______.
He said that light _______ much faster than sound. [ ]
A. traveled
B. will trave
C. travels
D. is traveling