[9.10.] Consider a competitive firm with a production function f:

with n inputs, each of which costs w, per unit, thatproduces two outputs that are priced at pi, with quantity qi, i = 1,2. A regulator is concerned with the firm producing too little andhence imposes a penalty for producing quantity less than Qi specifically, the penalty for underproduction of output i isλ(Qi - qi)Jli.e, the firm pays this amount if it produces less than Qi). Let w be the vector of cost {w1,w2} waJand , be the vector of{λ1 , λ2}

【題組】9. Which of the following statements are true?
(A)The firm's profit is concave in the vector w
(B)The firm's profit is convex in the vector w
(C)The firm's profit is both concave and convex in the vector w
(D)The firm's profit is neither concave nor convex in the vector w