与照片密度值成正比关系的是（）
A.照射量
B.摄影距离
C.被照体密度
D.被照体厚度
E.显影液的疲劳度
参考答案：A
Teenagers in the 1950s, who had to ______ an increasingly atomized family life and domestic and international tensions, scorned the sterile version of American life.
A．injure
B．conjure
C．confront
D．inflow
快速切断阀是从全开至全关阀门转动（）于一圈并能关严。
A、大；
B、刚好；
C、小.
