题干

一个物块置于粗糙的水平地面上,受到的水平方向推力F作用,推力F随时间t变化的关系如图甲所示,速度v随时间t变化的关系如图乙所示.取g=10m/s2,求:

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同类题1

根据短文内容,从短文后的选项中选出能填入空白处的最佳选项。选项中有两项为多余选项。

             ____She described all the things she had to do—one was to make her bed—from themoment she woke up until she flew out of the door for work.I suggested sheexperiment by not making her bed for two weeks.She was shocked,probably thinking I'd been raised by wolves in a forest.____

        Two  weeks later she went into my office beaming.She had left her bed unmade for thefirst time in 42 years? and nothing bad had happened.“And you know what?”she said.“I don't dry my dishes anymore,either.”

____One was discovering that she had choices in her life that she had never seenbefore.The other was giving herself permission to be less than perfect.Thisstory shows an important principle (原理)about managing time:No one can do it all.Eachof us has to make choices and accept trade­offs.The problem is,many people choose in ways that put themselves and theirhealth last.They take better care of their houses and cars than they do ofthemselves.____

         So   what is the solution?There's an easyway.Decide what you want in your life,andput that first.On a daily basis,thatshould include regular meals,enoughsleep and time with your family.Exercise,leisure,friendships and hobbies should also be regular aspects oflife.____ The choice is yours:whatevermakes you feel good about yourself and your life.Take a nap.Take a walk.Taketime to play the piano.Stop bringing your briefcase home from the office.Stopkeeping your house as clean as your mother kept hers .Fill more of your timewith want­to­dos instead of have­to­dos.

A.This woman had made two major breakthroughs (突破).

B.Above all,youneedn't do anything for yourself regularly.

C.They put everyone else's needs ahead of their own.

D.However,shewent along with my idea.

E.Most people do not take time to relax themselves.

F.The point is to do something for yourself every day.

G.A patient came to see me about the stress in her life.

同类题3

阅读下列短文,从每题所给的A、B、C和D四个选项中,选出最佳选项。

A

San Francisco Fire Engine Tours

San Francisco Winery Tour

   Running: February 1st through April 30th

   This delicious tour goes through the city on its way to Treasure Island where we will stop at the famous Winery SF. Here you can enjoy 4 pours of some of the best wine San Francisco has to offer.(Included in tickets price)

  Departing from the Cannery: Tell time upon request.

  Duration(时长):2 hours

  Price: $90


Back to the Fifties Tour

  Running: August 16th through August 31st

  This tour transports you back in time to one of San Francisco’s most fantastic periods, the 1950s! Enjoy fun history as we take you through San Francisco for a free taste of ice cream.

  Departing form the Cannery 5:00 pm and 7:00 pm

  Duration:2 hours

  Price:$90

Spooky Halloween Tour

  Running: October 10th through October 31st

  Join us for a ride through the historical Presidio district .Authentic fire gear (服装)is provided for your warmth as our entertainers take you to some of the most thrilling parts of San Francisco

  Departing from the Cannery:6:30 pm and 8:30 pm

  Duration :1 hour and 30 minutes

  Price: Available upon request

Holiday Lights Tour

  Running: December 6th through December 23nd

  This tractive four takes you to some of San Francis’s most cheerful holiday scenes. Authentic fire gear is provided for your warmth as you get into the holiday spirit.

  Departing from the Cannery 7:00 pm and 9:00 pm

  Duration: I hour and 30 minutes

  Advance reservations required.