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 our sun. Many countries are already using solar energy. Solar panels are placed on the roof 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; cars and buses will use solar power instead of gas by the year two thousand fifteen.
Decide whether the following statements are TRUE or FALSE.
Choose the best answer to each question
A. on houses' roofs B. on the sun C. on water heaters D. on cloudy days.
A. before 2015 B. before 2050 C. in 2015 D. in 2050