彩色电视机的白平衡是指接收黑白图像信号时，在任何对比度的情况下均不带任何彩色。
参考答案：对
九、课文原句填空（每空0.5分，共5分）
1. Polly found herself ______ _____ _____ a man standing with his hand _________ on her arm.
2. In 1066, the Normans conquered English and _______ ______ ______ the country.
3. Unfortunately, all the people were _______ _______, and _______ was the city.
城市热岛效应是指当城区平均气温比郊区一般至少高出( )时的热污染现象。
A．1～2℃
B．0.5～1℃
C．0.3～0.5℃
D．1.2～1.8℃
