The figure аbоve shоws the supply оf migrаnts to Econlаnd from Historyland. This is the relationship between the quantity Q (the number of migrants) and the wage differential ∆w between Econland and Historyland. Suppose, as represented by the blue dashed line, that the wage differential is ∆w = 6 and that it does not depend upon the number of migrants. D1 (who also goes by Donald1) has proposed to build a wall between Econland and Historyland. After the wall is built, migrants will have to pay $2 to smugglers to get them over the wall. What is the equilibrium level of migration after the wall is built?