题干

科学工作者为了探测海底某处的深度,向海底垂直发射超声波,经过2s,收到回波信号,海洋中该处的深度为____ m (声音在海水中传播的速度是1500m/s);若一列长200m的火车以36km/h的速度,匀速通过700m长的山洞,从火车头刚要进山洞到火车尾刚离开山洞共需要____分钟.
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1500,1.5

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      Eight days for just ¥12,000      

      Departure time:May,October 2012

      Includes:

     ●  Return flights from 6 China’s airports to Naples

     ●  Return airport to hotel transport

     ●  Seven nights’ accommodation at the 3­star Hotel Nice

     ●  Breakfast

     ● The service of guides

     ● Government taxes

     Join us for a wonderful holiday in one of the Europe’s most wonderful corners—Naples in Italy if you want to have a nice time in a beautiful small quiet place.The ancient Romans called the city “happy land” with attractive coastline,colorful towns,splendid views and the warm Mediterranean Sea.Your best choice for a truly memorable holiday!

     Choose between the peaceful traditional villages of Sant’ Agata,setting on a hillside six miles away from Sorrento,or the more lively and well­known international resort town of Sorrento,with wonderful views over the Bay of Naples.

    Breathtaking  scenery,famous  sights  and  European restaurants everywhere.From the mysterious Isle of Capri to the hunting ruins of     Pompeii,and from the unforgettable “Amalfi Drive” to the delightful resorts (度假胜地) of Positano,Sorrento and Ravello,the area is a feast for the eyes!Join us,and you won’t be disappointed!

    Price based on two tourists sharing a double room at the Hotel Nice.A single room,another ¥2,000.A group of ten college students,¥10,000 for each.

    Like to know more?Telephone Newmarket Air Holidays Ltd.on:0845 ­226 ­7788(All calls charge at local rates).