题目内容：
Ultrasonic devices were used to_________.
参考答案：
答案解析：
单选题：Ultrasonic devices were used to_________.
- 题目分类：英语(二)
- 题目类型：单选题
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If snow and ice covered areas begin melting,________.
If snow and ice covered areas begin melting,________.
According to the passage ,what is the main difference betwee
According to the passage ,what is the main difference between ritual and drama?A
Antarctica is colder than Arctic on average.
Antarctica is colder than Arctic on average.A．True B．False C．Not Given
第（34）题选
第（34）题选
根据下面资料，回答题 Alaska ① In 1858 Americans welcomed Alaska into t
根据下面资料，回答题 Alaska ① In 1858 Americans welcomed Alaska into the Union as the 49