Answer:
During the first hour, the water change was <em><u>2 feet (or 14 feet)</u></em>
Step-by-step explanation:
We know that the level of water in a water tank was 16 feet, and that by 8 hours, it was <em>empty</em>. To find the <u>change</u> in the water level per hour, we need to <u>divide</u> 16 by 8.
16 ÷ 8 = 2
Therefore, during the first hour, the water change was <em><u>2 feet (or 14 feet)</u></em>
Hope this helps! :D