B. 3,136l

A. CaCO₃ + H₂SO₄ -------> CaSO₄ + CO₂ + H₂O
B. COH₁₂O₆  ---^{lên men}----> C₂H₅OH + CO₂ 
C. C₂H₅OH + O₂ -----------> CO₂ + H₂O
D. Cu + H₂SO₄    -----------> CuSO₄ + SO₂ + H₂O

trees should be planted around the shool yard

1. doesn't she
2. did he
3. won't  they
4. can't she
5. do they
6. didn't he
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8. don't you
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10. am not
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1. craft
2. because of
3. variety
4. how
5. carved