. Có các dung dịch KOH, HCl, H2SO4 (loãng), các chất rắn Fe(OH)3, Cu và các chất khí CO2, NO. Có bao nhiêu cặp chất tác dụng được với nhau? A. 4 cặp chất. B. 5 cặp chất. C. 6 cặp chất. D. 3 cặp chất.

Choose the best answer.

I think you should buy _____  pack of mineral water instead. And you can also buy _____  snacks such as potato crisps, 3 kilos of mandarins, 2 kilos of apples, 3 bunches of bananas, ______  cookies and soft candies.

Choose the best answer.

We should decorate our living room with _____ orange banner. We also need ________  ribbons, balloons, party hats and costume.

Choose the best answer.

I think that ______ cauliflower is not enough for 3 people. Let’s buy one more.