tính nồng độ % về khối lượng của hợp chất ca(hco3)2

Mong mn giúp ạ Write the correct form of the word 1. Cats are ... (intelligent) than rabbits. 2. Ngan is ... (bigger) old than Minh. 3. China is ... (large) than the UK. 4. My garden is a lot ... (colorful) than this park. 5. Helen is ... (quiet) than her sister. 6. My Geography class is ... (boring) than my Math class. 7. My class is ... (big) than yours. 8. The weather this autumn is even ... (bad) than last autumn. 9. This box is ... (beautiful) than that one. 10. A holiday by the mountains is ... (good) than a holiday in the sea.

Tính mol của 100g dd H2SO4 98% Mn giúp mình với

1. Please go on (talk) ______. I don't want (wait) ______ anymore. 2. We regret (tell) ______ you that your requirements (refuse) ______ 2 days ago. 3. He regrets (buy) ______ that house because he hass to repair it every year. 4. Don't forget (do) ______ it. It's worth (remember) ______ that. 5. Fancy (live) ______ with someone who never stops (talk) ______. 6. We spend hours (type) ______ our homework. 7. You got used to (eat) ______ vegetables. 8. She is familiar with (sit) ______ here long time, 9. Don't (let) ______ your children (do) ______ everything she wants. 10. I advise (not stay) ______ with Jack. 11. She (ask) ______ you (do) ______ everything she wants. 12. I regret (give) ______ you my phone number. You are usually calling me at midnight. 13. She insists on (go) ______ on details. 14. He allowed us (smoke) ______ here. 15. She didn't allow (smoke) ______ here.

cho hình vuông abcd tâm O, cạnh a. xác định và tính véc tơ AB + véc tơ OC.

a,co2+cao-> b,ag+h2so4 loãng -> c,na2co3+kcl-> d,k2co3+h2so4-> e,agno3+fecl3 -> g,mg+s-> h,h2 +cl-> f, fe+cuso4->

viết tập hợp các số tự nhiên có hai chữ số trong đó : a)chữ số hàng chục nhỏ hơn chữ số hàng đơn vị là 5 b)Chữ hàng chục gấp bốn lần chữ số hàng đơn vị c) chữ số hàng chục nhỏ hơn chữ số hàng đơn vị tổng hai chữ số bằng 14

Cho PT x $x^{2}$ - 2mx -1 = 0 (1) Giải PT (1) khi m=1 CM PT (1) có 2 nghiệm pb

Hai góc bằng nhau có đối đỉnh với nhau hay không? Lấy ví dụ. Giúp mình nha

1,he was late .when he .....at the airpot,the plane..... a,has arrived/took off b,arrived/had taken off c,had arrived/took off d,had arrived/had taken off 2,the moon....around the earth a,has moved b,moves c,is moving d,will move 3,my brother.......a lot of things for the past five years a,does b,did c,is doing d,has done