Carrara , the city has academies of sculpture and fine arts and a museum of statuary and antiquities, and a yearly marble technology fair. The local marble is exported around the world, and marble from elsewhere is also fashioned and sculpted commercially here. The word "Carrara" likely comes from the pre-Roman (Celtic or Ligurian) element "kar" (stone), through Latin "carrariae" meaning 'quarries'. Carrara is twinned with: Carrara Carrara () is a city and "comune" in Tuscany, in central Italy, of the province of Massa and Carrara, and notable for the white or blue-grey marble quarried there. It is on the Carrione
Economic region of production that increases in both capital and labour are required to produce a given fixed quantity of output. The ridge lines are the combination of points where marginal product (MP) of one of the factors is zero. The theory entails that there is a limit to how much one factor can be substituted for another. When production reaches a point where substitution between the factors becomes impossible (MP), the isoquant becomes positively sloping. No rational entrepreneur will operate at a point outside the ridge lines (Region of Economic Nonsense). Economic region of production In economics, the economic region of production is