QEZ
2 giờ trước (16:21)

gọi x là độ cao ban đầu

vận tốc giây cuối \(v=\dfrac{1}{2}gt^2=\dfrac{1}{2}g\dfrac{2x}{g}=\dfrac{1}{2}.2x\)

vận tốc giây trươc đó \(v'=\dfrac{1}{2}g.\left(t-1\right)^2=\dfrac{1}{2}g.\left(\sqrt{\dfrac{2x}{g}}-1\right)^2\)

\(2v'=v\Rightarrow x=...\)

hình như có 2 nhiệm ấy bn

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Nguyễn Thị Kim Thư

Exercise 3: Rewrite each sentence in the conditional sentences.

1. You got into so much trouble because you didn't listen to me.

=>.................................................................................

2. We got lost because we didn't have a map.

=>....................................................

3. My brother is so unhealthy because he doesn't take any exercises.

=>...........................................................................................

4. She doesn't pay attention to her cooking so the food is horrible.

=>................................................................................

5. The father is busy right now, so he can't help his child.

=>......................................................................

6. Our classmate had bad marks because he didn't study for the test yesterday.

=>..........................................................................................................

7. Tell me the whole truth or I won't help you.

=>................................................

8. The computer broke down so I had to stop my work.

=>....................................................................

9. She is not a millionaire, so she can't buy a house in Tokyo.

=>.....................................................................................

10. Study hard or you won't pass the examination.

=>............................................................

11. He can't find a good job because he doesn't know how to use a computer.

=>.................................................................................................

12. Today isn't Sunday, so the pupils can't go swimming.

=>..............................................................................

 

Lazyboy
4 giờ trước (14:22)

Exercise 3: Rewrite each sentence in the conditional sentences.

1. You got into so much trouble because you didn't listen to me.

=>........If you had listened to me, you wouldn't have got into so much trouble.........................................................................

2. We got lost because we didn't have a map.

=>..........If we had had a map, we wouldn't have got lost..........................................

3. My brother is so unhealthy because he doesn't take any exercises.

=>........If my brother took some exercises, he wouldn't be unhealthy...................................................................................

4. She doesn't pay attention to her cooking so the food is horrible.

=>.........If she paid attention to her cooking, the food wouldn't be horrible.......................................................................

5. The father is busy right now, so he can't help his child.

=>.........If the father weren't busy right now, he could help his child.............................................................

6. Our classmate had bad marks because he didn't study for the test yesterday.

=>.......If our classmate had studied for the test yesterday, he wouldn't have had bad marks...................................................................................................

7. Tell me the whole truth or I won't help you.

=>..............If you don't tell me the whole truth, I won't help you. .................................

8. The computer broke down so I had to stop my work.

=>........If the computer hadn't broken down, I would have had to stop my work. ............................................................

9. She is not a millionaire, so she can't buy a house in Tokyo.

=>...........If she were a millionaire, she could buy a house in Tokyo...........................................................................

10. Study hard or you won't pass the examination.

=>.........If you don't study hard, you won't pass the examination....................................................

11. He can't find a good job because he doesn't know how to use a computer.

=>............If he knew how to use a computer, he could  find a good job .....................................................................................

12. Today isn't Sunday, so the pupils can't go swimming.

=>.............If today were sunday, the pupils could go swimming.................................................................

 

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Câu 3:

nCu=0,1(mol)

PTHH: Cu +1/2 O2 -to-> CuO

0,1)________0,05_____0,1(mol)

=>V(O2,đktc)=0,05.22,4=1,12(l)

=>CHỌN C

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Câu 2:

Cấu hình lưu huỳnh (S): 1s22s22p63s23p4 (Z=16)

=> Vị trí lưu huỳnh: ô số 16, nhóm VIA, chu kì 3.

Cấu hình Oxi (O): 1s22s22p4 (Z=8)

=> Vị trí Oxi: Ô số 8, nhóm VIA, chu kì 2.

Chúc em học tốt!

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Câu 1:

a) (1) MnO2 + 4 HCl(đ) -to-> MnCl2 + Cl2 +2 H2O

(2) 6KOH(đ) + 3 Cl2 -to-> KClO3 + 5 KCl +3 H2O

(3) 2 KClO3 -to->2  KCl +3 O2

(4) 1/2 O2 + Mg -to-> MgO

(5) MgO + 2 HCl -> MgCl2 + H2O

(6) MgCl2 +2 AgNO3 -> Mg(NO3)2 +2 AgCl (kt trắng)

 

 

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Khoá học trên OLM của Đại học Sư phạm HN