If a doctor orders 15 mg of MSO4 and the solution available is 25 mg/mL, how many mL are needed?

To determine how many milliliters are needed when the doctor orders 15 mg of MSO4 (morphine sulfate), and the solution available is 25 mg/mL, you can use the formula:

[

\text{Volume} = \frac{\text{Dose}}{\text{Concentration}}

]

Here, the Dose is 15 mg, and the Concentration is 25 mg/mL. Plugging the values into the formula gives:

[

\text{Volume} = \frac{15 \text{ mg}}{25 \text{ mg/mL}} = 0.6 \text{ mL}

]

This calculation shows that you need 0.6 mL of the solution to deliver the ordered 15 mg of MSO4. This is why the choice of 0.6 mL is the correct answer.