Which of the following describes what happens during a combustion reaction?
O
Two elements switch places with one another.
O
A larger compound breaks apart into smaller elements/compounds.
O A hydrocarbon combines with oxygen to release energy, carbon dioxide, and water
Two elements come together to form a new compound.

Where's the pictures ?

Engineers have contribute to society in many ways like making the technology we use today or any type of power energy material

The population of unionid mussels decreased after zebra mussels were introduced. zebra mussels competed with the unionid mussels for food. the zebra mussels were able to displace the unionid mussels, allowing the zebra mussel population to increase  over the years. the unionid mussel population decreased because  of lack of food.