1. Cho đá vôi CaCO3. Tính phần trăm theo khối lượng của cacbon trong phân tử. 2. Muối ăn gồm 2 nguyên tố hoá học là Natri và Clo, trong đó Natri chiếm 39,3% theo khối lượng. Tìm công thức hoá học của muối ăn, biết phân tử khối của muối ăn gấp 29,25 lần phân tử khối của hiđro.

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Mn giúp em vs ạ em đg cần gấp ạ I. Change the following sentences into the indirect speech, using the verbs in brackets: 1.Nga said “I am sorry I drop the jug. (apologized)  Nga apoligised for dropping the jug 2.The policeman said “the thief steals the bicycle”. (accused) The policeman accused the thief stole 3.The thief said “I don’t take the bicycle”. (denied) ------------------------------------------------------------------------------------------------------- 4.Tom said “he will drive Kate to the station”. (insisted) ------------------------------------------------------------------------------------------------------- 5.Ba said “I break the mobile phone”. (admitted) ------------------------------------------------------------------------------------------------------- 6.Lan said “Why don’t we go for a picnic on Sunday”. (suggested) ------------------------------------------------------------------------------------------------------ 7.David said “I always want to be a rich man”. (dreamed) ------------------------------------------------------------------------------------------------------- 8.He said to the boy “Don’t swim in that river” (warned) ------------------------------------------------------------------------------------------------------- 9. Jean said “No, it is not true. I didn’t steal the money!”. (denied) ------------------------------------------------------------------------------------------------------- 10.Peter said “Why don’t we go to the cinema this evening?” (suggested) -------------------------------------------------------------------------------------------------------- 11. David told “I ‘ve broken your pen. I ‘m sorry, Jack” (apologized) -------------------------------------------------------------------------------------------------------- 12. “No, no, I really must have another drink.” Dick said. (insisted) ------------------------------------------------------------------------------------------------------- 13. Jane said, “Let’s go to the Zoo, shall we?” (suggested) -------------------------------------------------------------------------------------------------------- 14. “Don’t touch that flower!” the old lady said to the boy. (warned) -------------------------------------------------------------------------------------------------------- 15. “Don’t use the telephone after eleven o’clock” (told) He said to me -------------------------------------------------------------------------------------------------------- 16. “Eat your meal!” (told) He said to his children. -------------------------------------------------------------------------------------------------------- 17. “You should give up smoking!” (advised) He said to me ------------------------------------------------------------------------------------------------------- 18. “I’ll go to the cinema with you” (promised) She said to me ------------------------------------------------------------------------------------------------------ 19.“Remember to pay the money to me.” (reminded) She said to me -----------------------------------------------------------------------------------------------------