A store sells lawn mowers, tillers, and chippers. They make a profit of $60 on each lawn mower, $25 on each tiller, and $50 on each chipper. Each product requires assembling and testing time. Lawn mowers require 4 hours of assembly time, tillers require 3 hours of assembly time, and chippers require 5 hours of assembly. Lawn mowers use 2 hours of testing time, and tillers and chippers each use 1 hour of testing time. There are 890 hours of assembly time and 600 hours of testing time available. The company must produce at least 100 lawn mowers and 130 tillers. The initial simplex tableau has: rows columns