Answer:
H2O2 H2O CO CO2 CH4 are all compounds.
Explanation:
 Compounds contains 2 or more ions of different elements in different proportion joined by chemical bonds into a molecule.
 
        
             
        
        
        
The Answer is C Gas exchange take place in our lungs
        
             
        
        
        
Alvin was a deep sea vehicle which was used to explore the depths of the ocean. It sunk but was recovered and recommissioned in 1973 after which it discovered black smokers, a special type of hydrothermal vent which produces super heated water with a highly acidic pH. Thus, the answer is B.
        
                    
             
        
        
        
when an animal eats plants they could be eating the carbon.
 
        
             
        
        
        
The answer is Event 1. A solar eclipse occurs when the moon gets between the sun and Earth and blocks the sunlight from reaching Earth's surface during daytime, thus casting a shadow over Earth. A lunar eclipse as represented by Event 2 happens when the moon passes into the shadow of Earth at night and we can see the moon darken.