The graph illustrates the activity level of three common digestive enzymes, across a range of ph values. calculate the ph range in which pepsin will be effective to some degee?

The graph shows that the activity of pepsin is zero at a pH level between 9-12. This means pepsin does not work properly in basic conditions.  The enzymes start to function slightly between pH 8 to 8.9. Below this pH, the activity of the enzyme, pepsin, gets better and better and it is most effective when the pH of the solution is round about 2. This graph illustrates that pepsin works best in acidic conditions.