Luke Skywalker was explaring forests on the Alderaan and found himself totally lost. He wants to contact his dear friend Yoda but does not know how. Suddenly, he finds an intergalactic videophone, The4s, conveninetly provided by Interstellar Telekom, which lists two mobile plans. First plan is unlimited and costs 20 Republic credits. The per-minute plan charges one Republic credit per minute. Luke Skywalker has the demand given by the equation QD=20-2P, where QD is the number of minutes he wants communicate and P is the price in Republic credits. Which plan should he choose? [Hint: it is safe to assume that Luke chooses the plan that maximizes consumer surplus from using The4s]