How many pounds of butterfat are in 1 gal of whole milk that weighs 8.6 lb and contains 4% butterfat?

1. Determine the weight of butterfat in the milk by multiplying the total weight of the milk by the percentage of butterfat: 8.6 \, \text{lb} \times 0.04 = 0.344 \, \text{lb}

2. Thus, the pounds of butterfat in the milk is: 0.344 \, \text{lb}