Cho tam giác ABC vuông tại A; BC = a không đổi, C ^ = α 0 0 < α < 90 0

Tìm góc để diện tích tam giác ABC là lớn nhất. Tính giá trị lớn nhất ấy.

A. α = 45 0 ; m a x S A B C = 1 2 a 2 .

B.  α = 30 0 ;  m a x S A B C = 3 4 a 2 .

C.  α = 60 0 ;  m a x S A B C = 3 4 a 2 .

D.  α = 45 0 ;  m a x S A B C = 1 4 a 2 .

Cho hình lập phương ABCD.A′B′C′D′ có cạnh bằng a. Tính diện tích xung quanh của hình trụ có hai đường tròn đáy ngoại tiếp hai hình vuông ABCD và A′B′C′D′.

A. S = πa 2 2 2

B.  S = 2 πa 2

C.  S = π 2 a 2

D.  S = πa 2

Circle the correct answer A, B, C, or D to complete each of the following sentences.

We go to the movies ________ Sunday evening.

A. to

B. at

C. on

D. for

A. nice

B. bicycle

C. ride

D. live

2 l

Choose the letter A, B, C or D to answer these following questions

Last week Nick and some of his classmates went to the countryside. They went to visit a farm of Nick’s uncle.

They left early in the morning and went there by bus. Nick’s uncle, Mr. Brown met them at the bus stop and took them to his farm. On the way, Uncle Brown showed them the field of wheat and vegetables where some tractors were running up and down, ploughing and breaking soil, distributing manure and planting potatoes.

After lunch, they all went for a walk. In the large yard of the farm, they saw some farm machines. Among them is the biggest machine which is called a combine harvester. They were told that this machine can cut and thresh corn at the same time.

In the afternoon, they went to the paddy field, the place where cattle such as horses, sheep and cows were raised. They were very excited to see how cows were milked by the workers there. Uncle Brown also spoke about many interesting things in the countryside. After having some fruits and cakes, they said goodbye and went home.

Question: What did they do before saying goodbye?

A. eating cakes

B. drinking beer

C. doing exercises

D. cutting trees

     1 : Số chia hết cho 2 thì phải có tận cùng là 0,2,4,6,8 . Ta có dãy số : 1000 , 1002 , ... , 9998 .

                                    Có tất cả số số có 4 chữ số chia hết cho 2 là : 

                                                ( 9998 - 1000 ) : 2 = 1 = 4500 ( số ) 

                                                                    Đ/S : 4500 số . 

2:                                                           Đổi 0.8 = 8/10 

                                Coi SB là 8 phần thì số lớn là 10 phần . Ta có sơ đồ : 

SB : ,___,__,___,___,__,___,__,___,

SL :  ,___,__,___,___,__,___,__,___,____,_____,_____,

 ( Để tui ăn cơm đã nhé rồi tối làm tiếp . ) 

548

Read the passage below and decide whether the statements are TRUE or FALSE?

I’m Bing. My grandmother told me that our village used to be very poor many years ago. The villagers had to work hard in the fields all day but they could not earn enough for their living. Their lives were very simple. Many people had to live in houses made of straw and mud. Nowadays my village has changed a lot. People live in big brick houses. In the evening, they can listen to the news on the radio or watch TV for entertainment. All people in my village try their best to make their living better. They raise and resurface the roads so that the roads will not be muddy and flooded after it rains.

Question: The road has been renovated to improve living standard.

A. True

B. False