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Principles of Programming Languages, 2013.02.13 Notes: - Total available time: 2h. - You may use any written material you need. - You cannot use computers, phones or laptops during the exam. Exercise 1, Haskell (5+6 pts) CBCB Inc. produces its goods (bikes and other stuff) by assembling various parts coming from several suppliers. CBCB is connected to its suppliers through a number of supply brokers, and each of them is specialized in dealing one type of item (e.g. wheels, components, brakes...). At a fixed scheduled times (say, once every three months) each broker sends to CBCB's server a message containing the current offers from its suppliers (e.g. of wheels). Such message is a sequence of offers of analogous items. CBCB's server enqueues such sequence in a sequence of sequences; when this is complete, the servers calls the procedure allPossibleBikes to return all the possible combinations of bikes that could be built. Example: supply broker 1 sends (ultra-wheel-1, WheelyWheel); supply broker 2 sends ("very nice frame", "another frame", "frame000"); supply broker 3 sends (3444,712,9938,115403). In this case allPossibleBikes should return the sequence: (ultra-wheel-1 "very nice frame" 3444) (WheelyWheel "very nice frame" 3444) (ultra-wheel-1 "another frame" 3444) (WheelyWheel "another frame" 3444) (ultra-wheel-1 "frame000" 3444) (WheelyWheel "frame000" 3444) (ultra-wheel-1 "very nice frame" 712) (WheelyWheel "very nice frame" 712) (ultra-wheel-1 "another frame" 712) (WheelyWheel "another frame" 712) (ultra-wheel-1 "frame000" 712) (WheelyWheel "frame000" 712) (ultra-wheel-1 "very nice frame" 9938) (WheelyWheel "very nice frame" 9938) (ultra-wheel-1 "another frame" 9938) (WheelyWheel "another frame" 9938) (ultra-wheel-1 "frame000" 9938) (WheelyWheel "frame000"…