光纤通信是以()为载波,以光纤为传输媒质的一种通信方式。 A.紫外线 B.红外线 C 发布时间:2021-02-25 22:58 │ 来源:www.tikuol.com 题型:单项选择题 问题: 光纤通信是以()为载波,以光纤为传输媒质的一种通信方式。A.紫外线B.红外线C.激光D.可见光
题型:单项选择题 A new survey shows that 54 percent of Americans do not take prescription medicines ________ though they are important to their health. [ ]A. as they instruct B. as were instructedC. as to be instructed D. as instructed 查看答案