C₆H₁₂O₆ + 6O₂ ➝ 6CO₂ + 6H₂O

\(PTHH:C_6H_{12}O_6+6O_2\rightarrow6CO_2\uparrow+6H_2O\)

pthh

C₆H₁₂O₆ + 6O₂ \(\underrightarrow{to}\) 6CO₂\(\uparrow\) + 6H₂O

\(2.16\ge2^n>4\)

\(2.2^4\ge2^n>2^2\)

\(2^5\ge2^n>2^2\)

=> \(n\in\left\{3,4,5\right\}\)

Vậy: \(n\in\left\{3,4,5\right\}\)

c b d a c b

30. C

31.B

32.D

33.A

34.C

35. B

Bạn ơi tách từng câu ra chứ :)

Bài 4: 

a: \(\Leftrightarrow5x\left(x-1\right)+\left(x-1\right)=0\)

\(\Leftrightarrow\left(x-1\right)\left(5x+1\right)=0\)

hay \(x\in\left\{1;-\dfrac{1}{5}\right\}\)

b: \(\Leftrightarrow x^2-6x+9-x^2-6x-9=24\)

=>-12x=24

hay x=-2

c: \(\Leftrightarrow x\left(x-2\right)\left(x+2\right)=0\)

hay \(x\in\left\{0;2;-2\right\}\)

d: \(\Leftrightarrow A=\dfrac{x\left(x-5\right)\left(x+5\right)}{x-5}=x\left(x+5\right)\)

e: \(\Leftrightarrow A=\dfrac{\left(x-y\right)\left(4-x\right)}{y-x}=x-4\)

2 It take more hours to travel by train than to travel

6 The bus run more frequently than the trains