Trong các phản ứng sau, phản ứng nào là phản ứng trao đổi? A. Na2O + H2O → 2NaOH. B. Ba(OH)2 + 2HNO3 → Ba(NO3)2 + H2O. C. 2Fe(OH)3 Fe2O3 + 3H2O. D. CuCl2 + Fe → FeCl2 + Cu.

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.