1. The sun directly provides light and heat resources to the earth. The growth and development of organisms on earth cannot be separated from the sun.
2. Solar radiation can maintain surface temperature and promote. the movement of water and atmosphere on the earth. The main driving force of biological activities
3. Fossil fuels such as coal and oil, which are the main sources of energy for industry, are solar energy fixed and accumulated by organisms throughout geological history
4. Solar radiation is our daily life The main source of energy for solar cookers, solar water heaters and solar power plants that can be used in life and production
Answer C
Analysis In fact, at a glance you can tell that there is. Both images represent the lighting images of the vernal and auto equinoxesmne, so the height of the sun at noon is also the same. , which means that only one of the two images has the correct angle. The height of the sun at noon on the spring and autumn equinoxes = 90° - local latitude. The height of the noon sun in Lhasa during the spring and autumn equinox = 90°-29°36'=60°24', then the angle of the heat collecting plate should be 90°-60° 24'=29°36'. The simplest thing to do is to remember that the angle of inclination of the heat collecting plate during the spring and autumn equinoxes is equal to the local latitude.