正弦电量的最大值就是有效值的根号2倍。()

A. 对
B. 错

物联网的基本特征不包含哪个方面？

A. 全面感知
B. 可靠传递
C. 智能处理
D. 数据交换

物联网是各种感知技术的广泛应用，目前它所利用的主要传感器类型包括哪些？

A. 射频识别技术（RFID）
B. 红外感应器
C. 二维码
D. 激光扫描器

物联网的核心和基础是（）。

The Romans led by Julius Caesar launched their first invasion on Britain in ____.

A. 200
B. 55 B.
C. 55 A.
D. 410 A.D

Under William the Conqueror, the _____ were at the bottom of the feudal scale.

A. knights
B. lesser nobles
C. freeman
D. serfs

Under _____, the feudal system in England was completely established.

A. HenryⅡ
B. William Ⅰ
C. Richard Ⅰ
D. Henry Ⅴ

The feudalism was ended by ______

A. the Wars of Roses
B. the Hundred Years War
C. the English Civil War
D. the Glorious Revolution

The Romanization was not so successful in _________

A. roads
B. baths
C. religion
D. language

Caesar’s death is still a mystery today.

A. 对
B. 错