4. (15 points) An oil tanker is being filled with oil at a rate of 5 barrels per minute. How much is this in cubic meters per hour? 1 barrel equals 159 liters.

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# Answer: $47.7 \mathrm{~m}^{3} /$ h.

Solution. $5 \frac{\text { barrels }}{\text { min }}=5 \frac{159 \text { liters }}{\frac{1}{60} h}=5 \cdot \frac{159 \cdot 0.001 \mathrm{~m}^{3}}{\frac{1}{60} h}=47.7 \frac{\mathrm{m}^{3}}{h}$.