Read the passage, then answer the questions below (2.5pts)

Are you looking for a cheap, clean, effective source of power that doesn't cause pollution or waste natural resources? Look no further than solar energy from the Sun.

At present, most of our electricity comes from the use of coal and gas, oil or nuclear power. This power could be provided by the Sun. One percent of the solar energy that reaches the Earth is enough to provide power for the total population.

Many countries are already using solar energy. Solar panels are placed on the roofs of a house and the Sun's energy is used to heat water. The energy can be stored for a number of days, so on cloudy days you can use solar energy, too.

Sweden has an advanced solar energy program. There, all buildings will be heated by solar energy and cars will use solar power instead of gas by the year 2015.

Questions: Is the solar energy used in Vietnam now?

Read the following passage, then choose the correct answer to questions.

Today, supermarkets are found in almost every large city in the world. But the first supermarket (26)_________ opened only fifty years ago. It was opened in New York by a man named Michael Cullen.

A supermarket is different (27)___________other types of stores in several ways. In supermarkets, goods are placed on open shelves. The (28)__________ choose what they want and take them to the checkout counter. This means that fewer shop assistants are needed than in other stores. The way products are displayed is another difference between supermarkets and many other types of stores; (29)___________ example, in supermarkets, there is usually a display of small inexpensive items just in front of the checkout counter: candies, chocolates, magazines, cheap foods and so on.

Most customers (30)___________ go to a supermarket buy goods from a shopping list. They know exactly what they need to buy. They do the shopping according to a plan.

Question 26:

A. is

B. has been

C. was

D. were

Có 1 mẫu dung dịch FeSO 4  bị lẫn tạp chất  CuSO 4 , có thể làm sạch mẫu dung dịch này bằng kim loại nào?

A. Zn

B. Mg

C. Fe

D. Cu