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如图所示,杠杆的B点挂着一个重物,在A点施加一个最小的动力使杠杆平衡.请画出最小的动力F1和它的动力臂 l1以及杠杆受到的阻力F2.

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解:如图所示:

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Top 5 Must See Places in Beijing

    Beijing is an old capital city with a lot of tourists attractions. What is the most representative place in Beijing? The answers are various. Here are the Top 5 Must See Places in Beijing.

1). Forbidden City

    The Forbidden City is the ideal place for you to begin your exploration of Beijing. Make sure to wear comfortable shoes as you have to walk a lot! A multilingual guide recorder is recommended, as it can tell you the stories behind the palace.

Opening Hour: 8:30-17:00

Entrance Fee: RMB 60

2). Tian'anmen Square

    Lying in the heart of Beijing City, it is the place for massive parades and gathering. It boasts of the largest square of such kind in the world. At sunrise and sunset the raising and lowering ceremony of the Chinese National Flag is well worth seeing.

Ticket fees: Free

Opening Time: Whole Day

3). Great Wall

    Most of the sections of the Great Wall in Beijing are well-preserved, and the most famous section is Badaling. For the Great Wall hiking, get ready for strong footwear. For hot weather, please also prepare sunblock, sunglasses and water.

Badaling Great Wall:

Ticket Fees: RMB40 (Nov. 01 to Mar. 31); RMB 45 (Apr. 01 to Oct. 31)

Open Hours: 6:40 to 18:30

4). Summer Palace

    Regarded as the largest imperial garden in China, the Summer Palace is in fact a park-styled royal retreat. With masterly design and artistic architecture integrating the highlight of Chinese garden arts, it has earned a title of "Royal Garden Museum".

Open Time: 6:30-20:30

Ticket Fee: RMB 40 (low season) / RMB 50 (peak season during the holidays)

5). Temple of Heaven

    The Temple of Heaven worked as sacrificial compound buildings for the Ming and Qing emperors. What's the intriguing by-production of the temple is that if you enter the Temple of Heaven in the early morning, you can find many people doing all types of Kungfu, Taiji, dancing and other morning exercises.

Open Time: 6:00-21:00

Ticket Fee: RMB 35