III. Modal verbs: S + modal verb + V(bare inf.) 1

. It isn’t necessary for you to wake up early.

=> You don’t ___________________________________________________ 2

. You are not allowed to make noise here.

=>You mustn’t _________________________________________________

3. Don’t stay up late every night.

=> You shouldn’t _______________________________________________

4. It’s better for you to review what you have learned.

=> You should _________________________________________________ 5

. It’s necessary to revise new words regularly.

=>You should _________________________________________________

Cho 4 số dương thỏa mãn điều kiện a+=c=2b ; c.(b+d)=2bd . cm (a+c/ b+d )^8 = a^8+c^8/ b^8+d^8

Part 5. Read the passage carefully and choose A, B, C or D to indicate the best answer to the questions.(1.0 point) Solar energy is a long lasting source of energy which can be used almost anywhere. To generate solar energy, we only need solar cells and the sun! Solar cells can easily be installed on house roofs, so no new space is needed and each user can quietly generate their own energy. Compared to other renewable sources, they also possess many advantages. Wind and water power rely on turbines which are noisy, expensive and easy to break down. Solar cells are totally silent and non-polluting. As they have no moving parts, they require little maintenance and have a long lifetime. However, solar energy also has some disadvantages. We can only generate solar energy during daytime because the system depends on sunlight. Besides, solar cells require large area to work effectively. The main disadvantage of solar energy is that it costs about twice as much as traditional sources such as coal, oil and gas. This is because solar cells are expensive. Scientists are hoping that the costs of solar cells will reduce as more and more people see the advantages of this environmentally friendly source of energy

40. What does the word advantages in line 13 mean?

A. very bad

B. resources

C. benefits

D. friendly

Cho Tv (M)=M'
a) M(3;-2)M Tìm M'
b) d: 2x-3y+5=0. Tìm d'
c) (P): y= (x-3)^2 . Tìm P
d) (C): (x−2 )^2 + y2 -4y+1=0. Tìm C'

 Bài 1:Phân tích đa thức sau thành nhân tử

a)12x^2-12x+3

b)3x.(x-2)+5.(2-x)

c)x^2-2x-y^2+1

d)81x^4+4

C.12/ Ở một TB sinh dục sơ khai gà trống(2n=78) sau một số đợt NP liên tiếp môi trường nội bào đã cung cấp 19890 NST đơn, các TB con được tạo ra đều trở thành TB sinh tinh, giảm phân cho tinh trùng. Hiệu suất thụ tinh của tinh trùng là 6,25%, của trứng là 50%. Theo lý thuyết, hãy XĐ:

a.Số lượng TB sinh tinh và số lượng TB sinh trứng cần thiết để hoàn tất quá trình thụ tinh.

b. Để hoàn tất quá trình thụ tinh, môi trường đã phải cung cấp bao nhiêu NST đơn. Biết rằng các TB sinh trứng được tạo ra từ một TB sinh dục cái ban đầu.