Suppose there is an output y produced from an input l. Let output price be p and input price be w. Technology is given by the function (0 if l 1 y=f(l)= l1 ifl1 It might really help to draw the diagram for this (labour on the horizontal, output on the vertical). What does the production function look like, roughly? (It is the constraint for the firm). In that diagram, what do iso-profit lines look like? (Those are the firm's 'indifference curves'.]