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

6 The bus run more frequently than the trains

1. Đáp án C

2. Đáp án C ( $K_2O,BaO,CaO,CuO,Na_2O,Fe_2O_3,MgO,ZnO$ ) 

$Al_2O_3$ là oxit lưỡng tính

3. Đáp án Sục khói than qua dung dịch nước vôi trong để hấp thụ hết khí độc 

$CO_2 + Ca(OH)_2 \to CaCO_3 + H_2O$
$SO_2 + Ca(OH)_2 \to CaSO_3 + H_2O$
$SO_3 + Ca(OH)_2 \to CaSO_4 + H_2O$

5 That is the farthest distance i have ever run

6 It was the worst mistake I have ever made

5 That's the furthest (or farthest) I've ever run.

6 It is/was the worst mistake I've ever made.

5. That run .... ( mình ko hiểu đề )

6. It make the worst mistake

ơ khoan '' The Mid - Second Term Test '' ? 

b: Tọa độ giao điểm là:

\(\left\{{}\begin{matrix}2x-3=-x+3\\y=-x+3\end{matrix}\right.\Leftrightarrow\left\{{}\begin{matrix}x=2\\y=1\end{matrix}\right.\)

\(2.16\ge2^n>4\)

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

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

=> \(n\in\left\{3,4,5\right\}\)

Vậy: \(n\in\left\{3,4,5\right\}\)