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Message: <blockquote data-quote="Happy" data-source="post: 6866543" data-attributes="member: 16762">Question 1 - Problem 508Units not shown, I hate it when they do that.A Unit Hydrograph is a hydrograph of of dropping 1 inch evenly on the watershed.  You get it by dividing every point on the hydrograph by the average excess precipitation.  So, where they hydrograph Q has units of cf/s, a unit hydrograph has units of cf/(s x in).Draw out the unit hydrograph with the 3 points given.  It goes up and down over a course of 3 hours.  The values are:Q1=0.5cf/(s x in)Q2=1.2cf/(s x in)Q3=0.4cf/(s x in)Now, the first hour you are given values in inch/hour.  The rain events last 1 hour.0.5 in/hr x  1 hour = 1.5 in0.7 in/hr x  1 hour = 0.7 inNow multiply for the first two hours, as asked for in the problem:0.5cf/(s x in) x 1.5 in   +   1.2cf/(s x in) x 0.7 in  =Now that should help you with your units, as you can see you'd wind up with cf/s.  However, to get the answer they did you would need to multiply 1.5x1.2 + .7x.5 = 2.15.  Are you sure you wrote the question up correctly?Question 1 - Problem 509Read through Step 3, page 20-16.  It appears that you need 'additional tables' for pasture land.  Table 20-5 is specified for cultivated land.I'm taking Transportation, so am only learning enough to get through the morning breadth.  Hopefully won't need to worry about the extra tables.</blockquote>