Final answer:
The minimum value within a 1 SD range of the average is 1.62 mL.
Step-by-step explanation:
To find the minimum value within a 1 SD range of the average, we need to subtract the standard deviation from the average. In this case, the average value is 2.3 mL and the standard deviation is 0.68 mL. Subtracting 0.68 mL from 2.3 mL gives us 1.62 mL. Therefore, the minimum value within a 1 SD range of the average is 1.62 mL.