Don't understand this one

SONY manufactures and sells digital clock radios. A major component for these is supplied by the electronics division of SONY. The cost functions for the radio and the electronic component divisions are, respectively, TCr = 30 + 2Qr ch = 70 + soc + QCZ Manufacture of one radio set requires the use of one electronic component. Market studies show that the rm's demand curve for the digital clock radio is given by Pr = 108 - Or a. Assuming no outside market for the components, how many of them should be produced to maximize prots for SONY as a whole? b. What is the optimal transfer price