The pH scale measures how acidic or basic a substance is. Normal drinking water needs to have a pH of less than 8.5 and greater than 6.5. Model the normal range of pH values of water, using a compound inequality.

6.5 < x < 8.5
6.5 ≤ x ≤ 8.5
6.5 ≥ x ≥ 8.5