To determine how much the amount of water in the canteen should change every 10 minutes, we first calculate the rate of water consumption per minute.
The recommended water consumption is 24 ounces per hour, which is equivalent to:
\[ \frac{24 \text{ ounces}}{60 \text{ minutes}} = 0.4 \text{ ounces per minute} \]
Now, to find out how much water is consumed in 10 minutes, we multiply the rate by 10:
\[ 0.4 \text{ ounces per minute} \times 10 \text{ minutes} = 4 \text{ ounces} \]
Therefore, the amount of water in the canteen should decrease by 4 ounces every 10 minutes.
The correct response is:
−4 ounces (negative 4 ounces)