<h2>A reference point is a starting point used to describe the position of an object.</h2>
Explanation:
<h3>A reference point is a place or object used for comparison to determine if something is in motion. An object is in motion if it changes position relative to a reference point. Objects that are fixed relative to Earth – such as a building, a tree, or a sign - make good reference points. </h3>
I'm going to say since I cannot see the graph i'm guessing that it shows an enzyme at its peak and lowering so i'm going to say the first one 1) There is a specific pH range in which the enzyme effectively lowers the reaction's activation energy
