为防止氧的有害影响，严格控制火焰性质和（）距离。
参考答案：焰芯到熔池表面
染色的全棉平纹机织帆布
—Have you got the information _____ you need to use for the report?
—Not yet. But I'll try to find some on the Internet at once. [ ]
A. which
B. who
C. what
D. whose
