该日志同步发布于帖子：“停车场的围墙” a parking lot fencing project was bid at us$11 per foot,and one company is doing all the work,the parking lot has four equal sides of 125 feet and requires the installation of a six-foot diameter culvert on one side.Fencing should be installed at a rate of 100 feet per day.The culvert installation will cost of US$500 and take one day to complet.The culvert must be installed before work can begin on that side of the fence.After threee days of work,one side complete,another has 75 feet installed,and the culvert ……