Mn giúp em làm bài tập này với ạ!
*Cho 4,48 lít khí CO2 (đktc) tác dụng vừa đủ với 200 ml dung dịch canxi hiđroxit thu được a(gam) muối:
a) Viết phương trình phản ứng xảy ra
b)Tính a
c)Tính nồng độ mol của Ca(OH)2 đã dùng

Mn giúp em làm bài tập này với ạ! Em cần gấp ạ!
*Chia dạng đúng của động từ trong ngoặc:

1.She (work) in the factory for 20 years before she moved
2.They (build) the fridge for 2 years by the end of this week
3.They are watching TV, they (watch) for 2 hours
4.By the years, the students (collect) 200 stamps
5.They seldom (paint) the picture when it (buy)
6.This is the highest building, Mr.Vuong (build)
7.It was the second time she (tell) me lie
8.By next week, we (collect) many stamps
9.The farmer (plant) this tree for years before it rained heavily
10.The workers (make) cars for 20 years now

Chuyển các câu sau sang bị động ( bị động đặc biệt - Special passive )

1. Who have they spoken to ?

2. What did they steal yesterday ?

3. Who have broken the windown?

4. The teacher had the student clean the ground

5. My sister sent me a computer

6. She made me cry

7. Nga got her friend to buy a pen

8. Mai is going to bring many plowers

9. Did he use to play soccer well?

10. Does he have to do exercises?

Mn giúp em làm bài tập này với ạ! Em cần gấp ạ!
* Rewrite the sentences:
1."Are you the new manager, Daisy?" said Bill (congratulate)
2."You can't run out of the garden" Mrs Kelly said to the children (prevent)
3."I didn't have the window" Bill said (deny)
4.''You told a lie, Tom'' she said (accuse)
5.''I can't go to your birthday party next Saturday evening, Jack'' said Mary (apologize)
6.''I won't help you with your homework. Never!'' Jane said to me (refuse)
7.Joe said'' Please come to my party'' (invite)
8.Mr.Gray said'' Don't play in the street'' (warn)
9.''Would you like to come on a picnic with us'' (invite)
10.''Please don't tell anybody what happened'' (ask)
11.''If you don't give me a pay rise. I'll resign'' (threaten)
12.''I'll finish the work by the end of this week" (promise)
13."You ought to take a break, Andrew" (advise)
14.''Don't forget to go to the supermarket after work" (remind)
15.''Stay away from me'' (warn)
16.''Why don't we sing a few songs?" (suggest)

Mn giúp mình làm bài tập này với ạ!
* Giải các phương trình sau( đặt ẩn phụ):
a)(x^2+x)^2 + 4(x^2+x) - 12 = 0
b)(x^2+2x+3)^2 - 9(x^2+2x+3) + 18 = 0
c)(x-2)(x+2)(x^2-10) = 72
d)x(x+1)(x^2+x+1) = 42
e)(x-1)(x-3)(x+5)(x+7) - 297 = 0
f)x^4 - 2x^2 - 144x - 1295 = 0

Tổng hai số đã cho là:42,95