(10 points) We denote by X the prot (in USD bn) of Microsoft in the third quarter of 2023, and by Y the prot (in USD bn) of Apple in the third quarter of 2023. A nancial analyst models the joint probability density function of X and Y by x )_ T185529 ifogggg3and03y2a ,y 0 otherwise. (a) (5 points) Show that f (x, y) is a joint probability density function. (b) (5 points) Compute the probability that Microsoft's prot is greater than 2 and Apple's prot is greater than 1