1. Convert mg to mcg:
75 \text{ mg} = 75000 \text{ mcg}
2. Calculate the concentration of the drug in the solution:
\text{Concentration} = \frac{75000 \text{ mcg}}{1000 \text{ mL}} = 75 \text{ mcg/mL}
3. Determine the infusion rate in mL/hr:
\text{Infusion rate} = 25 \text{ mL/hr}
4. Convert the infusion rate to mcg/hr using the concentration:
\text{Infusion rate in mcg/hr} = 25 \text{ mL/hr} \times 75 \text{ mcg/mL} = 1875 \text{ mcg/hr}
5. Finally, convert the infusion rate to mcg/min:
\text{Infusion rate in mcg/min} = \frac{1875 \text{ mcg/hr}}{60 \text{ min/hr}} \approx 31.25 \text{ mcg/min}
Therefore, the infusion rate is approximately 31.25 \text{ mcg/min} .