Hai hệ phương trình $\displaystyle \left\{ \begin{array}{l}kx+3y=3\\-x+y=1\end{array} \right.$và$\displaystyle \left\{ \begin{array}{l}3x+3y=3\\x-y=-1\end{array} \right.$ là tương đương khi k bằng:
A. 3
B. -3
C. 1
D. -1

Choose the best answer for the following sentence:
Hoai: ''How rich is your uncle?'' / Thu: ''He possesses all __________ you have seen''
A. Which 
B. that   
C. what  
D. where

Hệ phương trình tương đương với hệ phương trình $\displaystyle \left\{ \begin{array}{l}2x-5y=5\\2x+3y=5\end{array} \right.$ là
A. $\displaystyle \left\{ \begin{array}{l}2x-5y=5\\4x+8y=10\end{array} \right.$
B. $\displaystyle \left\{ \begin{array}{l}2x-5y=5\\0x-2y=0\end{array} \right.$
C. $\displaystyle \left\{ \begin{array}{l}2x-5y=5\\4x-8y=10\end{array} \right.$
D.  $\displaystyle \left\{ \begin{array}{l}\frac{2}{5}x-y=1\\\frac{2}{3}x+y=\frac{5}{3}\end{array} \right.$

Choose the best answer for the following sentence:
Mr. Lam goes to work on foot once a week. It means he _____________ walks to work.
A. never
B. sometimes
C. often
D. usually

Choose the word that has the underlined part pronounced differently from the rest:
constantly                 apply                   lovely                    specially
A. constantly                 
B. apply                   
C. lovely                    
D. specially

Choose the best answer for the following sentence:
I ____________ a bath every morning. It is my habit.
A. am having 
B. have
C. had 
D. will have

Tích phân $I=\int\limits_{0}^{{\frac{\pi }{2}}}{{\left( {{{{\sin }}^{4}}x+{{{\cos }}^{4}}x} \right)\left( {{{{\sin }}^{6}}x+{{{\cos }}^{6}}x} \right)}}dx$ bằng?
A. $\frac{{11}}{{128}}\pi .$
B. $\frac{{11}}{{64}}\pi .$
C. $\frac{{33}}{{128}}\pi .$
D. $\frac{{33}}{{64}}\pi .$

 có giá trị là:
A.
B. 5e4
C. 5e4 - 1
D.

Cho $y=f\left( x \right)$ là hàm số chẵn, có đạo hàm trên đoạn$\left[ -6;6 \right].$ Biết rằng$\int\limits_{-1}^{2}{f\left( x \right)\text{d}x=8}$ và$\int\limits_{1}^{3}{f\left( -2x \right)\text{d}x=3.}$ Tính$\int\limits_{-1}^{6}{f\left( x \right)\text{d}x.}$
A. $I=11$.
B. $I=5$. 
C. $I=2$. 
D. $I=14$.

Tích phân $I=\int\limits_{1}^{\sqrt[4]{3}}{\frac{1}{x({{x}^{4}}+1)}dx}$ bằng
A. $\frac{1}{4}\ln \frac{3}{2}.$
B. $\frac{1}{2}\ln \frac{3}{2}.$
C. $\frac{1}{4}\ln \frac{2}{3}.$
D. $\frac{1}{4}.$