nnêu đặc điểm nhận biết các đại diện của ngành lớp động vật
Cho hàm số y= (m-1)x + m +3
1) Tìm giá trị của m để đồ thị của hàm số song song với đồ thị hàm số y= -2x + 1.
2) Tim giá trị của m để đồ thị của hàm số đi qua điểm (1; -4).
3) Tìm điểm cố định mà đồ thị của hàm số luôn đi qua với mọi m.
4) Tim giá trị của m để đồ thị của hàm số tạo với trục tung và trục hoành một tam giác có diện tích bằng 1 (đvdt).
giúp mình câu này với ? Hỗn hợp E gồm X, Y, Z đều là este no, mạch hở (trong đó X, Y đều là este đơn chức và (MX < MY < MZ). Thủy phân hoàn toàn 0,16 mol E bằng lượng vừa đủ 220 ml dung dịch KOH 1M, thu được hỗn hợp F gồm hai muối của axit cacboxylic và 10,96 gam hỗn hợp T gồm hai ancol kế tiếp nhau trong dãy đồng đẳng. Mặt khác, đốt cháy hoàn toàn 0,08 mol E cần dùng 0,595 mol O2, thu được CO2 và H2O. Phần trăm khối lượng của Z có trong E là A. 25,93%. B. 39,69%. C. 45,39%. D. 59,53%
When referring to the overuse of antibiotics, the expression “too much of a good thing” can't help but come to mind. In many cases, antibiotics are absolutely necessary; for example, they can stop an ear infection from making you go deaf and they can even save your life after surgery. But why is it detrimental to take them too often?
Our immune system is our body’s first line of natural defense against infectious organisms. It protects us from bacteria and other microorganisms that can make us sick. In the past, people relied on their own bodies to cure them of illnesses, without the aid of medication or antibiotics. Nowadays, we often turn to antibiotics to do what our immune system used to do for us. And it’s not difficult to figure out why they're so popular. Antibiotics are an easy cure for many sicknesses and help the patient get out and about again in a very short time.
The problem is that, by relying too much on antibiotics, we are weakening our immune system. Just like our muscles, our immune system needs exercise to stay in shape. If it is not used, it becomes weaker, and thus increasingly more antibiotics are required to cure an illness. Years of overuse lead to a vicious cycle that is almost impossible to break.
The other important factor to consider is that our bodies contain both good and bad bacteria. The good bacteria are essential for our bodies to maintain a balance and in this way, prevent illnesses. They also help to fight off other bad bacteria which make us sick. Unfortunately, antibiotics cannot tell the difference between them, and once in our system, kill off both types. This again results in our getting sick more easily.
Question 71: What is the main purpose of the passage?
A. to explain why antibiotics are absolutely necessary
B. to argue that antibiotics do not allow people to recover
C. to warn people to be cautious with antibiotic use
D. to compare antibiotics to different types of therapy
Question 72: What is the relationship between the immune system and antibiotics?
A. They are both equally effective against infection.
B. They both work to fight off illnesses.
C. They are both a natural form of defense.
D. They both need time to cure the patient.
Question 73: According to the passage, why are antibiotics so well-liked?
A. They make our body stronger. B. They are easy to obtain.
C. They can cure all kinds of illness. D. They work very fast.
Question 74: How do antibiotics weaken our immune system?
A. They kill off bad bacteria. B. They prevent us from getting exercise.
C. They do its work so it gets less efficient. D. They decrease the strength of our muscles.
Question 75: in the third sentence of the fourth paragraph, what does they refer to?
A. illnesses B. our bodies C. antibiotics D. good bacteria
I. complete the sentences using to-infinitive form of the verb below
- arrive - pass - cook - go - be
- buy - study - receive - have - repair
1. my parents promised___me a shirt for my birthday.
2. she pretents___ill because she doesn't want to study.
3. Frank has never offered___dinner for his mother.
4. the decided___to a cinema.
5. Rosy usually fails___on time.
6.___good marks, we all need to study hard.
7. i always do my best___well at school.
8. the kids are happy the girf from thier uncle.
9. she doesn't know how___the broken bike.
10.it's difficult for them___that difficult exam.
II. complete the sentences using gerund or to-infinitive form of the verb in brackets.
1. we always look forward to___(hear) from them.
2.my father doesn't allow me___(go) out at satuday night.
3.would you mind___(close) the door ?
4.it's nice___(meet) you, Mr. Parker.
5. she adores___(sing) karaoke with friends.
6. our teacher wants us___(keep) silent in class.
7.it's no good___(invite) strange guests home.
8. when will you finishe___(eat) your breakfast ?
9. Henry agree___(register) in the summer camp.
10. she intends___(take) an extra english class.
Make questions for the underlined words or phrases
1. She went to school by bus yesterday
2. He bought this hat at the shop over there.
3. It took me three hours to finish my hmoework.
4. I need a phone card to phone my parents.
5. It’s about 500 km from Lai Chau to Ha Noi.
6. I saw her last night.
7. Her neighbor gave her a nice dress.
8. They returned to America two weeks ago.
9. Mrs. Robinson bought a poster.
10. My father was in Ha Noi last month.
11. He traveled to Nha Trang by train.
12. She went to the doctor because she was sick.
13. Nam left home at 7 o’clock yesterday.
14. He taught English in the high school.
15. The homework was very difficult yesterday.
16. There are many roses in the garden.
17. Liz will send these letters to her friends.
18. My favorite subject is Math.
19. I go to the movie once a week.
20. Yes, he is. (He is good at drawing)
21. Jonh went to Viet Nam in 2000.
22. My mother is cooking in the kitchen at the moment.
23. Yes, She does (Lan likes playing table tennis.)
24. It is very hot in summer.
25. My father is 60 kilos.
26. They stay in a hotel.
27. This ruler is 30 centimeters
28. That is her pen
29. It takes him 20 minutes to go to school by bike
30. My phone number is 0912……….
Cho mạch điện như hình vẽ.
Trong đó: Đ1: 6V − 6W; Đ2: 12V − 6W. Khi mắc hai điểm A và B vào hiệu điện thế U0 thì các đèn sáng bình thường. Hãy xác định:
a) Hiệu điện thế định mức của các đèn Đ3; Đ4; Đ5.
b) Công suất tiêu thụ của cả mạch. Biết công suất tiêu thụ của Đ3 là 1,5W và tỉ số công suất định mức của Đ4/Đ5 là 5/3.