皮皮学,免费搜题
登录
logo - 刷刷题
搜题
【单选题】
Singing Alarms Could Save the Blind If you cannot see, you may not be able to find your way out of a burning building -- and that could be fatal. A company in Leeds could change all that(51)directional sound alarms capable of guiding you to the exit. Sound Alert, a company(52)the University of Leeds, is installing the alarms in a residential home for(53)people in Sommerset and a resource centre for the blind in Cumbria.(54) produce a wide range of frequencies that enable the brain to determine where the(55)is coming from. Deborah Withington of Sound Alert says that the alarms use most of the frequencies that can be(56) by humans. 'It is a burst of white noise(57)people say sounds like static on the radio,' she says. 'Its life-saving potential is great.' She conducted an experiment in which people were filmed by thermal-imaging cameras trying to find their way out of a large(58)room. It(59)them nearly four minutes to find the door(60)a sound alarm, but only 15 seconds with one. Withington studies how the brain(61)sounds at the university. She says that the(62) of a wide band of frequencies can be pinpointed more easily than the source of a narrow band. Alarms(63)the same concept have already been installed on emergency vehicles. The alarms will also include rising or falling frequencies to indicate whether people should go up(64)down stairs. They were(65)with the aid of a large grant from British Nuclear Fuels.
A.
without
B.
with
C.
having
D.
selling
手机使用
分享
复制链接
新浪微博
分享QQ
微信扫一扫
微信内点击右上角“…”即可分享
反馈
参考答案:
举一反三
【简答题】抛物线上一点到焦点的距离是3,则该点到抛物线准线的距离
【单选题】设抛物线 上一点P到 y 轴的距离是3,则点P到该抛物线焦点的距离是(  )
A.
8
B.
6
C.
5
D.
4
【单选题】设抛物线y 2 =4x上一点P到直线x=﹣3的距离为5,则点P到该抛物线焦点的距离是(  )
A.
3
B.
4
C.
6
D.
8
【判断题】对既不需要结计本月发生额也不需要结计本年累计发生额的账户,可以只将每页末的余额结转次页。
A.
正确
B.
错误
【单选题】点P是抛物线y 2 =4x上一点,P到该抛物线焦点的距离为4,则点P的横坐标为(  )
A.
2
B.
3
C.
4
D.
5
【单选题】设抛物线y 2 =4x上一点P到y轴的距离是2,则点P到该抛物线焦点的距离是(  )
A.
1
B.
2
C.
3
D.
4
【单选题】24设抛物线 上一点P到y轴的距离是2,则点P到该抛物线焦点的距离是
A.
1
B.
2
C.
3
D.
4
【单选题】Was sind ihre Erwartung das Kind?
A.
für
B.
auf
C.
an
【判断题】溶液被加热到鼓起第一个泡时的温度称为泡点,气相混合物被冷却到有第一滴夜滴析出时的温度称为露点。
A.
正确
B.
错误
【单选题】(  )的设计是用来克服传统年金在通货膨胀条件下保障水平降低的缺点。
A.
即期年金
B.
延期年金
C.
定额年金
D.
变额年金
相关题目:
参考解析:
知识点:
题目纠错 0
发布
创建自己的小题库 - 刷刷题