David tunes pianos in his spare time for extra income. Buyers of his service are willing to pay $135 per tuning. One particular week, David is willing to tune the first piano for $115, the second piano for $125, the third piano for $140, and the fourth piano for $175. Assume David is rational in deciding how many pianos to tune. His producer surplus is __.

Jake and janelle loved to prepare gourmet meals for friends and family. they started a business of preparing theme-type dinners for friends who were having parties. to generate even more interest in the business, janelle created on her website. she posted pictures of events, and close-ups of the food they served. she encouraged patrons and others to post reviews, comments, and favorite recipes, and to share their own party ideas. her promotion became a dialogue between buyers of her service and the business. interactive promotion infomercials product placement broadcast