73 What is the runoff in cfs from a 020 square mile tract of

7-3 What is the runoff, in cfs, from a 0.20 square mile tract of land that has a weighted runoff coefficient, Cw -0.4 and an intensity of 2.87 in/hr?

Rational Equation: Q=ciA
The Rational equation requires the following units:
Q = Peak discharge, cfs
c = Rational method runoff coefficient
i = Rainfall intensity, inch/hour
A = Drainage area, acre

c = 0.4
i = 2.87 inch/hour
A = 0.2 X 640 = 128 acre ( 1 square mile = 640 acre)