Micron Technology has sales offices located in four cities: Dallas, Seattle, Boston, and Los Angeles. An analysis of the company's accounts receivables reveals the number of overdue invoices by days, as shown here. Days overdueDallasSeattleBostonLos AngelesTotalUnder 30 days13712219828774430-60 days85467610931661-90 days33275548163Over 90 days18324566161Total2732273745101384a What is the probability that a randomly selected invoice from the database is from the Boston sales office.bWhat is the probability that a randomly selected invoice from the database is between 30 and 90 days overdue?cWhat is the probability that a randomly selected invoice from the database is over 90 days old and from the Seattle office?dIf a randomly selected invoice is from the Los Angeles office, what is the probability that it is 60 or fewer days overdue?