In an adult human, approximately how much does 1 gallon of blood weigh?

• A. About 2 lb (approximately 0.9 kg)
• B. About 20 lb (approximately 9.1 kg)
• C. About 8 lb (approximately 3.6 kg)
• D. About 12 lb (approximately 5.4 kg)

Answer: (C)

Verified step by step guidance

1. Understand that the problem asks for the approximate weight of 1 gallon of blood in an adult human.
2. Recall that the density of human blood is roughly 1.06 grams per milliliter (g/mL), which is slightly denser than water.
3. Convert 1 gallon to milliliters: 1 US gallon is approximately 3,785 milliliters (mL).
4. Calculate the mass of 1 gallon of blood by multiplying the volume by the density: mass = volume \times density, or \(mass = 3785 \text{ mL} \times 1.06 \text{ g/mL}\).
5. Convert the mass from grams to pounds or kilograms using the conversion factors: 1 pound = 453.6 grams, and 1 kilogram = 1000 grams.