光源许可宽度
参考答案：
光源临界宽度的四分之一，此时干涉条纹的可见度为0.9。
单向匿名式评价，有利于专家独立思考、独立判断及（）。
girls took part in the Happy Girl Competition but only few of them succeeded.
A．Million of
B．Many million of
C．One million of
D．Millions of
