Answer:
The Sun's rays warm our world, stir air and ocean currents, and catalyze chemical reactions in the atmosphere. The Sun-warmed surface evaporates water to form rain clouds that redistribute fresh water around the world. And sunlight is essential for most life forms that live at Earth's surface.
Explanation:
 
        
             
        
        
        
Answer:
A
Explanation:
Coal is majorly used to produces electricity. The coal is ignited and the heat produced used to heat water to steam. The steam is then used to drive turbines with a dynamo effect to produce electricity. Turning off lights when not in use reduces the demand for electricity hence reducing the amount of coal needed to meet this demand. 
Other ways to conserve energy is using bulbs with low energy demand - such as LEDs - and  improving natural lighting indoors. 
 
        
             
        
        
        
Answer: this is the correct answer for PLATO
 
        
             
        
        
        
Alveoli are found in lungs and exchamge O2 and Co2 !!
so answer is last one !!