Find a mistake in the four underlined parts of the sentence and correct it:
We would visit you had we known you were in hospital.
A. would visit
B. had
C. known
D. were

Find a mistake in the four underlined parts of the sentence and correct it:
Alike football, a water polo game begins with the ball in the centre of the pool.
A. Alike
B. game
C. with
D. in the centre

Find a mistake in the four underlined parts of the sentence and correct it:
What I told Tom was a secret. He shouldn’t have been repeated it to you.
A. told
B. was
C. been repeated
D. to you

Find a mistake in the four underlined parts of the sentence and correct it:
Higher general education is based on theoretical expertise and might be contrasted with higher vocational
education, which concentrating on both practice and theory.
A. is based on
B. expertise
C. contrasted with
D. concentrating

Find a mistake in the four underlined parts of the sentence and correct it:
I enjoyed talking to the people with that I met at the party last night.
A. talking
B. the
C. with that
D. at the party

Find a mistake in the four underlined parts of the sentence and correct it:
In 2030, how we will provide for the food, land, and energy needs of a global population of over 8 billion?
A. In 2030
B. we will provide
C. needs
D. over 8 billion

Cho hình chóp $S.ABDC$, với đáy$ABDC$ là hình bình hành tâm$O;AD,SA,AB$đôi một vuông góc$AD=8,SA=6$.$(P)$là mặt phẳng qua trung điểm của$AB$ và vuông góc với$AB$. Thiết diện của$(P)$ và hình chóp có diện tích bằng?
A. 20
B. 16
C. 17
D. 36

Cho hàm số  . Khẳng định nào sau đây đúng nhất 
A. Hàm số liên tục tại 
B. Hàm số liên tục tại mọi điểm 
C. Hàm số không liên tục tại tại  
D. Tất cả đều sai

Cho hàm số. Tìm  để liên tục tại .
A.  
B.  
C.  
D.

Đạo hàm của hàm số f(x) = (x2 + 1)4 tại điểm x = -1 là:
A. -32.
B. 30.
C. -64.
D. 12.