如图,某沿海开放城市A接到台风警报,在该市正南方向260km的B处有一台风中心,沿BC方向以15km/h的速度向D移动,已知城市A到C的距离AD=100km,那么台风中心经过多长时间从B移到D?如果在距台风中心30k

如图,某沿海开放城市A接到台风警报,在该市正南方向260km的B处有一台风中心,沿BC方向以15km/h的速度向D移动,已知城市A到C的距离AD=100km,那么台风中心经过多长时间从B移到D?如果在距台风中心30k
如图,某沿海开放城市A接到台风警报,在该市正南方向260km的B处有一台风中心,沿BC方向以15km/h的速度向D移动,已知城市A到C的距离AD=100km,那么台风中心经过多长时间从B移到D?如果在距台风中心30km的圆形区域内都有受到台风破坏的危险,为了让D点的游人脱离危险,游人必须在接到台风警报后的几小时内撤离?

如图,某沿海开放城市A接到台风警报,在该市正南方向260km的B处有一台风中心,沿BC方向以15km/h的速度向D移动,已知城市A到C的距离AD=100km,那么台风中心经过多长时间从B移到D?如果在距台风中心30k
(1) AB=100km AD=60km
∵AD⊥BC
∴BC=√(AB^2-AD^2)=√(100^2-60^2)=80km
80/20=4h
答:台风中心经4小时从B移到D
(2) 当台风中心移动到距D点30千米之间,游人必须撤离,所以此时台风中心移动的最大距离是
80-30=50km
在这段时间内,游人撤离都是安全的.
50/20=2.5h

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刚才那个人愚弄你，我将他的英文翻译后为：
（记者李辉博），昨日上午10时许，北京市海淀区学清路，静淑东里小区，用菜刀砍该公司负责人的家长培训。 PW物业工作人员说，折扣保守党伯奇，在现场的人说了好几次讨论没有结果后，出此下策的，因为金钱纠纷。

在蜀经学清路，东丽区，1号机组，4层的事件。明海物业海，一位工作人员说，听到呼喊楼上是一拼，他和几名保安迅速赶到楼上。打开...

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刚才那个人愚弄你，我将他的英文翻译后为：
（记者李辉博），昨日上午10时许，北京市海淀区学清路，静淑东里小区，用菜刀砍该公司负责人的家长培训。 PW物业工作人员说，折扣保守党伯奇，在现场的人说了好几次讨论没有结果后，出此下策的，因为金钱纠纷。

在蜀经学清路，东丽区，1号机组，4层的事件。明海物业海，一位工作人员说，听到呼喊楼上是一拼，他和几名保安迅速赶到楼上。打开门，发现一个50岁的男子坐在沙发，茶几上的一个血淋淋的菜刀在他面前。

曼说，孩子们收到这家公司的培训，保守党伯奇拖鞋，支付培训费用的数千美元，他认为该公司没有满足孩子的训练承诺，打算返回的钱，但不是在事发前到所有的钱追逐回。他来到这里，讨论几次，保守党伯奇网点，终于出此下策是谁负责。

头部被砍伤的公司一直躺在客厅背后的磨砂玻璃，与血头。员工拨打急救电话。随后999急救人员和东升派出所赶到现场。砍人男子被警方控制。

昨天下午，记者在清河急救中心看到，999人受伤。他的头部裹着纱布，不想接受记者采访。急诊室的医生说，病人没有生命危险。随后，记者来到发展公司，这里是北京中国国际教育咨询有限公司，公司方舟的办公室，公司锁门。记者在公司的网站上看到中写道，通过系统的专业教育和学习公司，为国际豪华邮轮培养出来的学生提供高质量，高素质的员工队伍。

PW物业工作人员证实，该公司已经建立了几年，已经做了乘务员和其他培训。事件公司的办公室和培训基地在昌平。海淀警方称，具体原因仍在调查。
题目简单，列方程啊。

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(Reporter Lihui Bo ) about 10 o'clock yesterday morning , Xue Qing Road , Haidian District, Jing Shu Dong Li district , a parent training with a kitchen knife to chop the head of the company . PW Prop...

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(Reporter Lihui Bo ) about 10 o'clock yesterday morning , Xue Qing Road , Haidian District, Jing Shu Dong Li district , a parent training with a kitchen knife to chop the head of the company . PW Property staff said ,discount tory burch, the perpetrators at the scene said several times to discuss the dispute because of money without result after such an unwise move .

incident in the Shu Jing Xue Qing Road, Dongli district , Unit 1, 4 layers. Ariake Sea of property , said a staff , was heard shouting upstairs was a fight , he and several security quickly rushed upstairs . Open the door and found a 50 -year-old man sitting on the sofa, coffee table in front of him on a bloody kitchen knife .

Man said the children had received training in this company ,tory burch flip flops, paid thousands of dollars in training costs , he believes the company did not meet the child 's training commitment , intention to return the money , but not before the incident until all the money chase back . He came here and discuss who is responsible for several times,tory burch outlets, finally an unwise move.

head was chopped company has been lying on the living room behind frosted glass , the head with blood . Employees call the emergency telephone. Followed by 999 emergency personnel and Dongsheng police station rushed to the scene. Knives to injure the man by the police control .

Yesterday afternoon , reporters at the Qinghe Emergency Center to see 999 injured . His head was wrapped in gauze , do not want an interview with reporters . Emergency room doctors said the patient no danger . Subsequently, the reporter went to the Development Corporation , here is the Beijing China International Education Consulting Co., Ltd. Ark 's office , the company locked the door . Reporters saw at the Company 's Web site wrote , the company through the system of professional education and learning , the students trained for international luxury cruise lines to provide high quality , high-quality staff .

PW Property staff confirmed that the company has been established a few years , have done flight attendants and other training. Incident to the company's office , and training base in Changping . Haidian Police said the specific cause is still under investigation .

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