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如图甲所示,放在水平地面上的物体,受到方向不变的水平拉力F的作用,F的大小与时间t的关系如图乙所示,对应的物体运动速度v与时间t的关系如图丙所示,分析图象可知,当t=1s时,物体受到的摩擦力为____N,当t=3s时,物体受到的摩擦力为____N.

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2,4

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Discovering Tasmania

    The island of Tasmania is separated from mainland Australia by the Bass Strait. The island is a place of natural beauty and has more than 2,000 km of walking tracks and 18 national parks. If you go on a tour, you'll discover a wild and beautiful place where the people are friendly and the food is delicious. If you don't like walking, there are other tours you can choose from including a river cruise and cycling. You can also combine your tour with fishing, sailing or sunbathing on the beach. 

    One of the most incredible places to walk is along the Tarkine coast which is located in the north-west of Tasmania. It's such a wild and remote area that you can easily complete your walk without seeing anyone apart from the members of your group and your two guides. The area contains the largest temperate rainforest in Australia which is home to more than 50 endangered species. It is also home to many Aboriginal Heritage Sites. Your guides will provide you with plenty of information about the area as you complete that part of your tour. During your tour, you'll come across rivers, mountain ranges, spectacular waterfalls, wildlife and long wild beaches. It will be an experience you won't easily forget. 

Tour Itinerary:

Day 1:

    You're picked up from your hotel in the town of Launceston and driven to the Tarkine. You then complete a three-hour walk through the forest before arriving at your camp at Mystery Creek. There you will enjoy a delicious meal cooked by your guides.

Day 2:

    After breakfast, you continue deeper into the rainforest, passing some of the tallest trees in the world as you go, and stopping for lunch and then camp in the evening.

Day 3:

    The highlight of today's hike is the Tarkine Falls, a beautiful 15-metre waterfall.

Day 4:

    Today you can stay at the camp and bathe in the Tarkine Falls, or you can go for a day hike for more fantastic views of the forest.

Day 5:

    After a last hike through the forest, you are picked up at about 4:00 p.m. and you arrive in Launceston at around 7:00 p.m.

    The tour includes two professional guides, transport to and from the rainforest, all food while on the tours and all safety equipment. You should buy or hire recommended camping equipment including: backpacks, sleeping bags, sleep mats, head torches, rain coats and trousers.

同类题2

诗文默写。
①不信,                                         ,是他们提着灯笼在走。(郭沫若《天上的街市》)
②                        ,白露为霜。(《诗经·秦风》)
③八百里分麾下炙,                             ,沙场秋点兵。(辛弃疾《破阵子·为陈同甫赋壮词以寄之》)
④                                          ?满眼风光北固楼。(辛弃疾《南乡子·登京口北固亭有怀》)
⑤念天地之悠悠,                                              。(陈子昂《登幽州台歌》)
⑥有一种品质叫无私,,有一种情感叫无悔,把它化作李商隐《无题》中的诗句,那便是“                                         ,                                          ”。
⑦潭西南而望,                                             ,                                            。(柳宗元《小石潭记》)
⑧请写出连续的两句与鸟有关的古诗词。                                   ,                                     。
⑨请写出连续的两句中抒发忧国忧民情怀的古诗词。                                         ,                                       。