7th grade happy summer vacation questions, 7th grade winter vacation homework questions

1.Gansu Province, Crescent Spring, Mingsha Mountain, etc.

2.Hunan Province, *** former residence, Shennong Valley, Yuelu Mountain, etc.

3.Natural heritage, Sichuan Province, Qingcheng Mountain, Wolong Nature Reserve, etc.

4.Cultural heritage, Shandong Province, Mount Tai, Baotu Spring, etc.

5.Natural heritage, Jiangxi Province, Jinggang Mountain, Tengwang Pavilion, etc.

6.Cultural heritage, Yunnan Province, Xishuangbanna, Kunming Stone Forest, etc.

7.Cultural heritage, Anhui Province, Huangshan, Jiuhua Mountain, etc.

8.In addition to the above, there are: the Great Wall, the Ming and Qing Dynasty Forbidden City, the Summer Palace, the Temple of Heaven, the Zhoukoudian "Pekingese" site, the Chengde Summer Resort and the surrounding temples, the ancient city of Pingyao, the Dazu stone carvings, the Mausoleum of the First Qin Emperor, the Suzhou Garden, the ancient buildings of Wudang Mountain, the Potala Palace in Lhasa, Mount Tai, the Yellow Mountain, Mount Emei, the Leshan Giant Buddha Scenic Area, the Huanglong Scenic Area, the Lushan Scenic Area, the Wuyi Mountain Scenic Area.

1. Mogao Grottoes Scenic Area, Gansu Province.

2. Feitan Waterfall, Hunan Province.

3. Former residence of Zhan Tianyou, Hubei Province.

4. Heihu Spring, Shandong Province.

5. Yuanyang Lake Scenic Area, Jiangxi Province.

6. Guanyin Gorge Scenic Area, Yunnan Province.

7. Anhui Province Huangshan Yungu Villa.

The Great Wall, the Forbidden City of Beijing, the Mausoleum of the First Qin Emperor and the Terracotta Warriors and Horses Pit, the Zhoukoudian Peking Man Ruins, the Taishan Scenic Area, the Huangshan Scenic Area, the Wulingyuan Scenic Area, the Huanglong Scenic Area, the Chengde Summer Resort and the surrounding temples, the ancient buildings of Wudang Mountain, the Potala Palace, the Emei Mountain-Leshan Giant Buddha

5. Plants include herbaceous plants and woody plants.

6. The characteristics of herbaceous plants are (xylem is less developed to underdeveloped) 7. The characteristics of woody plants are (xylem is developed).

8. Animals include (vertebrates) and (invertebrates.

9. Vertebrates include (mammals), (birds), (reptiles), (amphibians), (fish).

10. The characteristics of mammals are (there is hair on the surface of the body, which is generally divided into five parts: head, neck, trunk, limbs and tail; breathe with your lungs; has a constant body temperature and is a homeothermic animal; The brain is large and well developed; Suckle; Viviparous. Mammalism and viviparity are the most distinctive features of mammals. ）

11. The characteristics of reptiles are ().

12. Amphibians are characterized by ().

13. The characteristics of birds are ().

14. The characteristics of fish are ().

15. The characteristics of insects are ().

16. The characteristics of bacteria are ().

17. The characteristics of the virus are ().

18. The characteristics of fungi are ().

19. The condition for food mold is ().

20. If water resources, forest resources, biological resources, and atmospheric resources are destroyed, what disasters will this bring to mankind?

Look it up in the textbook yourself, right? It's not difficult! Good luck with your studies!

5。Herbaceous and woody plants.

6. The stems are relatively loose and soft.

7. The stem is relatively tight and hard.

8. Vertebrates and invertebrates.

9. Mammals, reptiles, amphibians, birds, fish.

We have no history of = =.

5.Naked seeds and quilts.

Question 1: To prevent sandstorms, we should plant more trees to purify the air.

Question 2: 1 e

2－－b3－－d

4－－c5－－a

Question 3: Photosynthesis: 2, 3, 6, hail resistance 7

Respiration: 1, 4, 5, 8

Question: grinding silver 1: yA = 120 (2+x) y B = 144 (1+x) Ask Dan You False Question 2: 4 people.

Question 3: A accounting.

It is not possible to see the mold burning, not the absolute value multiplication: [-15,6]The absolute value is multiplied: [4,15].

1) Let the homework book be x, then 4x+x+4=6, so the homework book is yuan, 2) Let the win be x, and the draw will be y, then 3x+y=22 x+y=10 Calculate it yourself.

Thank you for the trouble to adopt!

Answers to summer vacation homework.

24 (6 points) The "Iron and Steel Industry Adjustment and Revitalization Plan" issued in March 2009 proposed that by 2011, China's iron and steel industry should achieve significant results in energy conservation and emission reduction. The comprehensive energy consumption per ton of steel of key large and medium-sized enterprises does not exceed 620 kg of standard coal, the new water consumption per ton of steel is less than 5 tons, the emission of soot and dust per ton of steel is less than l 0 kg, and the carbon dioxide emission per ton of steel is less than l 8 kg.

The density of water is known Water = 1 0x103 kg m3, and the calorific value of standard coal Q = 3 4 107 J kg. Seeking:

1) The volume of 5t water.

2) The heat emitted by the complete combustion of 620kg of standard coal.

25 (6 minutes) As shown in Figure L2, it is part of the circuit of Xiao Li's house, and the lamp L is marked with "220V40W". He inserted an electric kettle with a resistance wire of 40 ohms into an socket and found that it took 5 minutes to boil a full pot of water, and the heat generated by the resistance wire of the electric kettle was 3 105j. If the resistance of the filament and the resistance wire does not change with temperature, find:

1) What is the actual voltage between the live wire and the neutral wire?

2) What is the actual power of lamp L when switch S is closed?

4. Experiment and ** questions (l4 points in total).

26 (6 marks) Figure 13 is the experimental device AB of "How to generate induced current", which is a conductor connected to the two binding posts of the sensitive galvanometer through wires and switches.

1) In this experiment, if so, we assume that there is an induced current.

2) After the switch is closed, if the conductor does not move, the magnet moves horizontally left and right, and the circuit induces current (optionally "Yes" or "None").

3) Xiao Li's experimental team wants to further **"What factors are related to the size of the induced current?" Xiao Li guessed: "It may be related to the speed of the movement of the conductor cutting the magnetic inductance line." ”

Please help Xiao Li design an experiment to test her conjecture according to the experimental setup shown in Figure 13

27 (8 points) In the experiment "What factors are related to the magnitude of friction", an object is pulled at a constant speed in the horizontal direction, and based on the existing knowledge, do you think the reason is:

In the experiment, the students put forward the following conjectures:

a is related to the amount of pressure b is related to the roughness of the contact surface.

c is related to the size of the contact area, d is related to the speed of the movement.

1) Xiao Yang used a long wooden board with a flat surface, a wooden block with a hook and a spring dynamometer to conduct experiments, such as:

Figure 14. The data records he devised are shown in the table below: Counts.

It should be divided as follows: 1 and 12, 2 and 11, 3 and 10....