. Suppose two rms. 1 and 2, produce cell phones. lOne of the companies uses operating system X and the other operating system Y. The demand for cell phones for rm i=l,2 is: 'i'i = at Pi + P: Assume the production of cell phones is costless, so that the prot lnction for rm i=l,2 is: \"i = Pig: a. Derive the price lnctions for rms 1 and 2. 13. Suppose a,- represents advertising expenditures for rms i=l,2, how do prices change with changes in own advertising expenditures? How do prices change with the "rival\" rm's advertising expenditures? c. Suppose advertising expenditures