You need to calculate the volume of water in a 50-foot long, 2-inch diameter pipe. The radius is 1 inch. Using the formula Volume = π x r² x L, what is a critical step before applying the formula to get a usable volume measurement?

• Multiply the length by 12 to convert feet to inches.
• Use the diameter instead of the radius in the formula.
• Convert the radius from inches to feet.
• Divide the final volume by 7.48 to get gallons.