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图为一水平传送带装置示意图,绷紧的水平传送带AB始终保持某一恒定的速率v运行,一行李无初速地放在A处,传送带对行李的摩擦力使行李开始运动,并在传送带右端脱离传送带.下列说法正确的是(   )

A:传送带运行速率v越大,行李在传送带上的运动时间一定越短

B:不管传送带运行速率v多大,行李一定能在水平段末端B脱离传送带

C:若行李释放后一直加速到末端B脱离传送带,则在空中的水平位移达到最大

D:若行李释放点改在A处右侧,则行李运动到末端B的速度可能不变

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C,D

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    A trip to Paris is not complete without a visit to the Eiffel Tower. To get the most out of your visit, read our tips below:
    Visit at Night
    Riding up the Eiffel Tower at night and looking out over the streets of Paris, you'll see why Paris is known as the “City of Light”. At street level, the spotlights on the top of the Tower zoom across the Paris skyline, and the reflections of the Tower in the Seine are sights not to be missed.
    Purchase Your Ticket in Advance Online
    Bypass the long ticket lines at the Eiffel Tower by purchasing your ticket online from the Eiffel Tower website. You'll pick a time to visit, and then select whether to print out the ticket or display it on your phone or iPad, which is a convenient option if you buy your ticket in Paris without easy access to a printer.
    Don't Bring Valuable Objects with You
    Before entering the Eiffel Tower, your bags will be examined by a security officer. If an item you are carrying sets off the metal detector, the officer will take you away from the line for further inspection. We've stood in line for hours witnessing people who missed their chance to go up the Eiffel Tower.
Have Drinks and Snacks at the Eiffel Tower
    If you're like us, after an exciting trip to the Eiffel Tower, you'll be ready to rest your legs and have a relaxing snack and a drink in a Parisian cafe. Across the Seine in the Trocadero area, there are many elegant cafes. The atmosphere is great, but the prices are in the stratosphere (最高水平). Actually, the perfect place for common visitors to eat and drink is on the Eiffel Tower itself.