1234-1234=0

Xe thứ 3 trở được là:

    (25+35):2=30(tấn)

              Đ/S:....

k nha

21 + 22 = 84 vì sai

Ta có :

\(\frac{a}{1}=\frac{b}{2}=\frac{c}{3}\)và a + b + c = 180 ^o

Áp dụng tính chất của dãy tỉ số bằng nhau ta có :

\(\frac{a}{1}=\frac{b}{2}=\frac{c}{3}=\frac{a+b+c}{1+2+3}=\frac{180^0}{6}=30^0\)

=> a = 30 ^o

     b = 60 ^o

     c = 90 ^o

Vậy a = 30 ^o , b = 60 ^o , c = 90 ^o

cách làm thì ko biết, nhưng kq thì CÓ LẼ là : M < 0,5

do M= 0,4783935314...  < 0,5

1. We want to share our recycling story with our________.

A. reading B. reader C. readers D. read

2. Air is a ______ of gases.

A. mix B. mixing C. mixture D. mixed

3. This is our new ________. Please try it!

A. production B. produces C. producing D. product

4. We are _______ that you are interested in protecting the environment.

A. delight B. delighted C. delighting D. delights

5. Mix them with certain specific ________.

A. chemistry B. chemicals C. chemist D. chemist’s

6. Contact an organization _______ Friends of the Earth ______ more information.

A. in – on B. for – on C. of – for D. like – for

7. Don’t throw things ______.Try and find another use ______ them

A. away – for B. away – in C. off – on D. off – for

8. We can look ____ information ______ recycling things in the local library.

A. after – for B. for – on C. up – in D. into – for

9. Milk ______ to houses by the milkman every day.

A. brings B. is bring C. is brought D. has brought

10. We were delighted _____ your letter last week.

A. getting B. to get C. get D. got

11. Milk bottles can be ______ after being cleaned.

A. recycled B. thrown away C. broken D. reused

12. One ton of recycled paper ______ approximately eight trees.

A. saves B. save C. is saving D. are saving

13. This project _____ next month.

A. are carried out B. carries out C. will carry out D. will be carried out

14. It’s dangerous ______ in that river.

A. swim B. to swim C. swimming D. swam

15. We are looking forward to _____ you in June.

A. seeing B. see C. saw D. be seen

16. Glass is broken up, melted and made ______ new glassware.

A. in B. to C. into D. from

17. I think we should use tree leaves such as banana leaves, lotus leaves, etc. ______ things.

A. to wrap B. to soak C. to recycle D. to protect

18. Clothes belong to ____ group. We can recycle them and make them into paper or shopping bags.

A. compost B. fabric C. junk D. vegetable matter

19. Melt the mixture ______ it becomes a liquid.

A. until B. when C. after D. before

20. My sister likes sweets ______ from chocolate.

A. make B. to make C. made D. making

chỉ có thể có 3 số là x

{231;242;253}

hết rùi

Cách 1:

Quãng đường thứ 1 tốn số lít xăng:

      138x12:100=16,56 ( l )

Quãng đường thứ 2 tốn số lít xăng:
      182x12:100=21,84 ( l )

               ĐS: 16,56 l

                     21,84 l

Cách 2:

Đi 1 km thì tiêu thụ số lít xăng:

      12:100=0,12 ( l )

Quãng đường thứ 1 tốn số lít xăng:

      0,12x138=16,56 ( l )

Quãng đường thứ 2 tốn số lít xăng:

     0,12x182=21,84 ( l )

            ĐS: 16,56 l

                   21,84 l

có 2 cách, làm cách nào miễn hiểu bài là được