Suppose fiat recently entered into an agreement and plan of merger with case for $4.3 billion. prior to the merger, the market for four-wheel-drive tractors consisted of five firms. the market was highly concentrated, with a herfindahl-hirschman index of 3,195. case’s share of that market was 16 percent, while fiat comprised just 8 percent of the market. if approved, by how much would the postmerger herfindahl-hirschman index increase?