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A. An earthwork contract requires to cut and move excavatedrocks. The site is a typical limestone rock formation in a cutsection, which is 15,000 ft long, 85 ft wide, and 3 ft deep.Seismographic tests indicate a seismic wave velocity of 5,000 fpsfor the rock layer material. The contractor proposes to rip therock with a 370-hp crawler tractor. Answer the followingquestions.

(a) Calculate the production in bcy per hour, for full-timeripping, with efficiency based on a45         -min hour.Assume that the ripper is equipped with a single shank and thatripping conditions are average (i.e., intermediate between extremeconditions). This is classified as heavy ripping.

(b) Estimate the ripping unit-production cost in dollars per bcyusing your calculated hourly production. The normal O&O costper hour, including operator, for a tractor w/ ripper $130.00. Theoperator’s wage with fringe is $33.00 per hour.

(c) What is the total direct cost of the cut quantity?

(d) What is the total duration of the rock cut project assuming10 hours per day work?

B. As a Construction Manager for this site development project,prepare detailed cost estimate for the project, and biddocuments.

      Assume 10% time value cost ofmoney, bonds, insurance, and storage over total direct cost,contingency at 2% of total direct cost, indirect overhead cost at5% of total direct cost (additional on top of the equipment andoperator costs), and 10% fee (on subtotal total of direct andindirect cost).