A survey of engineering firms reveals that 80% have their own mainframe computer (M); 10% anticipate purchasing a mainframe computer in the near future (B); and 5% have a mainframe computer and anticipate buying another in the near future. Find the probability that a randomly selected firm:
(a) has a mainframe computer or anticipates purchasing one in the near future
(b) does not have a mainframe computer and does not anticipate purchasing one in the near future
(c) anticipates purchasing a mainframe computer given that it does not currently have one
(d) has a mainframe computer given that it anticipates purchasing one in the near future Are the events M and B independent? Explain.