Rewrite the sentences without changing their original meanings.
1.   Students will take courses at their own pace.
      Courses_____________________________________________________________________________
2.   We will get online lectures from the internationally famous professors for our personal learning needs.
      Online lectures ____________________________________________________________________ 
3.   Students will study complex topics beyond the textbook.
      Complex topics ____________________________________________________________________ 
4.   The computer will make a joke to wake you up when you feel sleepy.
      A joke ___________________________________________________________________________ 
5.   Viet Nam will give the necessary resources and trust to all teachers.
      The necessary resources and trust _____________________________________________________ 
6.   The artificial intelligence will replace human minds in the next century.
      Human minds ___________________________________________________________________ 
7.   Local governments in rural areas will offer sufficient support to primary and secondary students.
      Sufficient support _________________________________________________________________ 
8.   Students will learn new skills through cool tools, videos, quizzes and game-like labs.
      New skills ________________________________________________________________________

 1) Tìm m để mỗi pt có nghiệm kép

a) mx^2 + (2m-1)x + m+2=0

b) 2x^2 -(4m+3)x +2m^2 -1=0

2) giải pt

x^2 -(m-1)x - 2m-2=0

cho pt x^2-(2m+1)x+2m-3=0 luôn có nghiệm phân biệt

Complete the story with " a/an/the or x (no article) "

1. There was_____ knock on ____ door. I openned it and found ___ small dark man in ____ blue overcoat and _____ woolen cap

2. He said he was ___ employee of_____ gas company and had come to read ____ meter.

3. But I had ____ suspicion that he wasn't speaking ___ truth because ____ meter readers usually wear ___ peaked caps.

4. Howerver, I took him to ______ meter, which is in ____ dark corner under _____ staris.

5. I asked if he had _____ torch; he said he dislike torchs and always read ____ meters by _____ light of_____ match.

Một gen có 80 vòng xoắn. Trong đó hiệu số nucleotit loại A và G là 250 nu.

a) Tính số nu, chiều dài và khối lượng của đoạn gen trên.

b) Tính nu mỗi loại.

c) Gen đột biến có A= 526 nu, X= 274 nu. Vậy đây là dạng đột biến gì? Tại sao?

Tập hợp $S$ gồm các số tự nhiên lẻ từ $3$ đến $88$.

Sắp xếp các phần tử của tập $S$ theo thứ tự tăng dần thì phần tử thứ $9$ của dãy là:...... giúp mik với