A contractor is placing soil in 10-in. loose lifts, each at about 85 pcf. The moisture content is 8% at the time of placement. The optimum water content for this soil is 10%.The contractor has a water truck with a spray bar on the back. How fast should the truck move with the spray running at some flow rate? Make a plot of gal/min from the spray bar (ordinate) versus speed of the truck in mph (abscissa) for the driver to use. Use a spreadsheet to create the data and corresponding plots. Extra credit: Make a similar plot, for a soil with a 6% initial water content. (After D. Elton)?