一个三维层的Diffuse属性控制：（）
参考答案：灯光的发散级别
For many cities in the world, there is no room to spread out further, _______ New York is an example.
A．for which
B．in which
C．of which
D．from which
安全阀应装设排汽管，其截面积至少为安全阀总截面积的（）倍，并直通室外。
A、1.5
B、2
C、2.5
D、3
