Please choose the correct ending to complete the given sentence: Home and Garden: [header] How to calculate roof runoff [title] Determine the footprint of your structure (f) in square feet : [substeps] Measure along the length of the house or building and along the width of the house or building (in feet). Multiply the two figures together to obtain the square footage of your roof. [title] Determine the percentage of water collected from each downspout (p).

Ending1: [substeps] Compare a edin rate of about 90% to how much water comes out (p-). It is important to compare a edin rate of about 90% with how much water is collected in each downspout (e). Ending2: [substeps] Count the number of downspouts coming from your roof. Divide 100 by the number of downspouts in order to obtain the percentage of water collected from each downspout. Ending3: [substeps] Obtain a fine scale of the gross gross water collected (r). Divide the gross liquid by the p (p). Ending4: [substeps] For the year, the average amount of water derived from one downspout (p) is 500 hrs. For a city or county, the average amount of water collected from another downspout (p) is 300 hrs.

Answer format: ending1/ending2/ending3/ending4