Answer:
B. Better ways to recycle plastics 
Explanation:
A chemist might choose to study better ways to recycle plastics because there may be certain types of chemicals that can disintegrate the plastic.. 
 
        
             
        
        
        
a balanced chemical equation occurs when the number of the atoms involved in the reactants side is equal to the number of atoms in the products side.
 
        
                    
             
        
        
        
Answer:
100 cm³
Explanation:
Hi there!
Subtract:
400 cm³ - 300 cm³
= 100 cm³
Therefore, the volume of the object is 100 cm³.
I hope this helps!
 
        
             
        
        
        
I would have to say no. There are metamorphic rocks, igneous rocks, and sedimentary rocks. Igneous rocks are rocks that have solidified from magma or lava upon cooling, like lava rocks. Sedimentary rocks are rocks from smaller sediments, such as sandstone being made from, well, sand. Metamorphic rocks are the result of preexisting rocks in a response to changes in the environment. This includes changes in pressure, air temperature, mechanical stress, as well as taking away or adding chemical components. Metamorphic can be from igneous, sedimentary, or any other metamorphic rocks. Hopefully this help (with the added bonus that I explained all three type of rocks.