题干

下列说法中正确的是()

A:功率大的机械做功多

B:机械效率高的机械做功多

C:功率大的机械效率高

D:功率大的机械做功快

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答案(点此获取答案解析)

D

同类题1

阅读理解

    Take part in one of these FUN summer camps.ID Tech Camps offer weeklong courses at locations throughout the US.Our junior courses provide additional time for off-computer activities,ensuring a well-balanced day.Learn from instructors who are passionate about technology.There is a maximum of just 8 students per instructor.Just choose a course.

    Adventures in Games Design

    Ages: 7-10

    Dates: July 1-July 7

    Cost: $520

    Don't just play games!Make them!Create your own video game in this fun,exciting video game camp for kids. Design your own arcade or platform game using professional software.Take breaks to play sports outside and do other activities.

    Adventures in Programming

    Ages: 7-13

    Date: July 4-July 10

    Cost: $750

    Let your imagination run wild in this multimedia adventure.Create your own interactive stories,animated adventures and creative comics.Learn drag-and-drop programming basics with scratch (a project of the MIT Media Lab).Computer characters are at your command!Take breaks with supervised outside sports and activities.

    Adventures in Robotics

    Ages: 12-15

    Date: July 4-July 10

    Cost: $1,200

    Imagine it,build it and watch it go!Powered by the LEGO MINDSTORMS Education NXT Base Set and Software,our Adventures in Robotics course explores the exciting world of robots!This course will have you create cool robots on your first day.

    Introduction to Web Design & Photography

    Ages: 9-12

    Date: July 14-July 20

    Cost: $700

    Use a high-end camera and learn the building blocks of web design with Adobe Dreamweaver.Put your photos into your basic website,and then share your creation with your friends and family.The software Adobe Flash may be introduced based on a student's progress throughout the week.

Movie Making Camp

    Ages: 12-15

    Date: July 14-July 20

    Cost: $1,8000

    Are you ready to learn the basics of filming and editing?

    Shoot with professional cameras and see how much fun creative editing can be with the video editor iMovie. Take home a DVD of your final project to show your family.Please remember it takes filmmakers years to master their skills.Please have realistic project expectations.

同类题3

任务型阅读

    We all have to make decisions all the time, and we have an abundance of choices, ranging from tiny issues to vital ones. Unfortunately, people often find it hard to make decisions____ If you would like to improve your skill of decision making, here are four suggestions for you. Don't expect to have it all.

    ____ You can't order every delicious dish on the menu. And there will be paths not taken, careers not chosen, to name a few. You can imagine some “what if' situations if you must, but do not let them take up too much space in your brain.

    ____

    It's often good to think through your decisions. But don't overdo it. Research can reach a point where returns begin to reduce, which makes it confusing more than clarifying. Many good decisions can be made based as much on intuition (直觉) as on careful assessment of endless data.

    Don't delay making decisions.

    Yes, there is a time to put off making a decision. Perhaps you need more information____ Or it's likely that you wait for a less stressful time. Just don't wait so long that the decision is made by your own indecisiveness.

    Don't be hard on yourself.

    You decide to go on a voyage. You choose an expensive liner. Everything should work out just right. Only you didn't expect a bug that ran around on the ship, making you and your family sick for five days____But please remember it is unavoidable sometimes.

A. Don't spend too much time thinking.

B. It is an important source of information.

C. Don't count on emotion to make decisions.

D. Maybe you wish to consult with your advisor.

E. You may regret making such a stupid decision.

F. That means the skill of good decision-making counts a lot.

G. Decisions force us to close the door on other possibilities.