1)

I wish i can play guitar well

2)

It took my mother three hour to make s dress

3)

The last time we were to the concert in last year

4)

He enjoys reading newspaper in the morning

5)

We haven't seen our grandfather for two years

6)

Payment can be made at any post ofice by you

Sings / very / beautiful / she

=> She sings very beautifully

is / Our / and / large / school / yard/ beautiful

=> Our school yard is large and beautifull

him / tells / storys / grandmother / every night / his / the

=> His grandmather tells him the story every night

chán

TT^TT

luk nãy Phương An on có một chút

Chán

Chán

Chán

\(\frac{89}{120}\)

Cho 200ml dung dịch A gồm : NH₄⁺ ; K⁺ ; SO₄^2- và Cl^- với nồng độ lần lượt là : 0,5M; 0,1M; 0,25M và xM . Tính lượng chất rắn thu được khi cô cạn 200ml dung dịch A: 

A. 8,09g 

B. 7,38g

C. 12,18g

D. 36,9g

Ta có sơ đồ:
Gạo nếp: |-----|
Gạo tẻ:    |-----|-----|-----|-----|-----|                         hiệu: 480 kg
Hiệu số phần bằng nhau là:
5 - 1 = 4 (phần)
Số gạo nếp có là:
480 : 4 x 1 = 120 (kg)
Số gạo nếp ó là:
480 : 120 = 600 (kg)

\(=\left(x^7-x\right)+\left(x^2+x+1\right)\)

\(=x\left[\left(x^3\right)^2-1^2\right]+\left(x^2+x+1\right)\)

\(=x\left(x^3-1\right)\left(x^3+1\right)+\left(x^2+x+1\right)\)

\(=x\left(x^3+1\right)\left(x-1\right)\left(x^2+x+1\right)+\left(x^2+x+1\right)\)

\(=\left(x^2+x+1\right)\left[x\left(x-1\right)\left(x^3+1\right)+1\right]\)

\(=\left(x^2+x+1\right)\left[x^2\left(x^3+1\right)-x\left(x^3+1\right)+1\right]\)

\(=\left(x^2+x+1\right)\left(x^5+x^2-x^4-x+1\right)\)