Answer:
The most recent common ancestor of all currently living organisms is the last universal ancestor, which lived about 3.9 billion years ago. ... 6,331 groups of genes common to all living animals have been identified; these may have arisen from a single common ancestor that lived 650 million years ago in the Precambrian.
 
        
             
        
        
        
Enzymes are not reactants and are not used up during the reaction. Once an enzyme binds to a substrate and catalyzes the reaction, the enzyme is released, unchanged, and can be used for another reaction. This means that for each reaction, there does not need to be a 1:1 ratio between enzyme and substrate molecules.Answer:
Explanation: now gimmie that coochie luigie
 
        
             
        
        
        
<span>All the options (heat, pressure, deposition and chemical environment) are correct.<span>
Metamorphic rocks are formed when pre-existing rocks are subjected to heat, pressure and hot mineral rich fluids which cause physical, chemical and mineralogical changes to the rock. Metamorphic rocks are grouped by chemical, texture and mineralogy. The common metamorphic rocks include schist, marble, and gneiss.  
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