Cho ΔABC, E ∈ BC, F ∈ AC sao cho AE = 4cm, AB = 6cm, AF = 6cm, FC = 3cm. Cho góc AFE = 40°. Tính góc C.

I. Choose the best answer A, B, C or D to complete each sentence

1. What is the main_______of visual pollution? - Because there are too many advertising billboards.

A. effect B. affect C. result D. cause

2. Households________waste into the river so it is polluted.

A. damage B. lead C. lose D. dump

3. If the factory ________ dumping poison into the lake, all the fish and other aquatic animals will die.

A. continues B. to continue C. continued D. will continue

4. Water pollution is the ________________ in the lake has made the fish die.

A. contaminating B. contaminate C. contaminated D. contamination

5. If I were you, I ______________ that car .

A. would buy B. buy C. bought D. buying

6. If the factorycontinues dumping poison _______ the lake, all the fish and other aquatic animals will die.

A. into B. to C. about D. in

II. Word form

7. The polluted water results in the _________of many aquatic animals DIE

8. If we use water __________________ . more people will have fresh water. CARE

9. Are all types of pollution ____________________ to the health of humans and animals? HARM

10. The music club made so much noise that the_________________ complained to its owner. RESIDE

III. Rewrite the sentences below without changing their original meaning

11. Leaves are damaged. The tree cannot get enough food energy to stay healthy. (because)

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12. Light pollution happens. There is a change in animals’ living patterns. (If)

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13. Factories release fumes. The air breathe gets polluted. (due to)

…………………………………………………………………………………………………

I. Choose the best answer A, B, C or D to complete each sentence.

1. Noise pollution can lead to________loss.

A. looking B. hearing C. listening D. reading

2. If I____a millionaire now, I____travel around the world. But in fact, I am very poor and have no money.

A. were/ would B. am/ will C. were/ will D. am/ would

3. Water ________________ in the lake has made the fish die.

A. pollution B. pollute C. polluted D. polluting

4. Have you come_______solutions to this problem?

A. up to B. up with C. to with D. on to

5. Mi and Nick like ______________ back Mi’s home village on holiday.

A. comes B. come C. came D. coming

6. Ships spill oil in oceans and rivers. This results________the death of many aquatic animals and plants.

A. to B. in C. from D. at

II. Word form

7. The____________fish are floating in the water. DIE

8. The river is________________by the dumping from nearby factories. CONTAMINATE

9. Noise pollution can also lead to headaches and high blood____________. PRESS

10. Dumping _________________waste into the lakes and rivers has caused serious water pollution. INDUSTRY

II. Rewrite the sentences below without changing their original meaning.

11. Radioactive pollution is very dangerous. It can cause abnormal growth. (since)

................................................................................................................................................

12. I don’t have much money now, but I want to buy a house in Phu Cuong. (If)

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13. They are interested in comets. They decided to study astronomy. (due to)

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Cho ΔABC nhọn, có AB<AC. Đường cao BE và CF cắt nhau tại H, M là trung điểm của BC, K đối xứng với H qua M. Chứng minh :

a. Tứ giác BHCK là hình bình hành

b. BK ⊥ AB, CK ⊥ AC

c. Gọi I là điểm đối xứng với H qua BC. Chứng minh : Tứ giác BIKC lả hình thang cân.

d. BK cắt HI tại G, ΔABC cần thêm điều kiện gì để tứ giác GHCK hình thang cân?

Tính hóa trị của nguyên tố chưa biết trong hợp chất

3/ Tính hóa trị của nhóm SO₄; NO_3; PO₄; CO₃ trong hợp chất :

a. Na₂SO₄

b. NaNO₃

c. K₃Po₄

d. K₂CO₃

Tính hóa trị của nguyên tố chưa biết trong hợp chất

2/ Tính hóa trị của nguyên tố Fe lần lượt có trong hợp chất :

a. FeO

b. Fe₂O₃

Tính hóa trị của nguyên tố chưa biết trong hợp chất

1/ Tính hóa trị của nguyên tố N lần lượt có trong hợp chất :

a. NO

b. NO₂

c. N₂O₃

d. N₂O₅

Kể tên một số bản vẽ thường dùng và công dụng của chúng.

1. Thế nào là phép chiếu vuông góc ? Phép chiếu này dùng để làm gì ?