根据公式H=F×b/a，以下叙述错误的是（） A.H表示几何模糊 B.F表示焦点尺寸
题型：单项选择题 A1/A2型题
问题：
根据公式H=F×b/a，以下叙述错误的是（）
A.H表示几何模糊
B.F表示焦点尺寸
C.b表示焦-片距
D.a表示焦-肢距
E.H=0.2mm为模糊阈值
题型：单项选择题 A1/A2型题
根据所给汉语提示，写出空缺处单词正确形式。
1. He was one of the greatest Chinese writers of the 20th _____ (世纪).
2. Lao She's Teahouse gives a wonderful _____ (欢迎) to everyone from China
and from all over the world.
3. It takes us to s
ee the teahouse as the _____ (中心) the neighbourh
ood.
4. Lao She wrote many _____ (戏剧) in his life.
5. There are many _____ (观众) in the cinema.