Which element listed above would have four electrons in it's outer energy level

Depends which elements are listed.

However, I will tell you that the first shell can only be occupied by a maximum of two electrons and the rest after that can have a maximum of 8 :)

Explanation:

answer by yourhope:

answer is

human impact on the environment can be seen in the deterioration of the !

: )

enzyme active site and substrate specificity

enzymes bind with chemical reactants called substrates. there may be one or more substrates for each type of enzyme, depending on the particular chemical reaction. in some reactions, a single-reactant substrate is broken down into multiple products