单项选择题 Michael Bayley, Marketing Director of UniPower’s Electrical Division, is leading a study to identify and assess the relative importance of product features. Michael directs his staff to design a survey questionnaire for distribution to all of UniPower’s 954 customers. For this study, the set of 954 customers is a （）.

单项选择题 Penny Bauer, Chief Financial Officer of Harrison Haulage, suspects irregularities in the payroll system, and orders an inspection of ‘each and every payroll voucher issued since 1 January 2005’. Five per cent of the payroll vouchers contained material errors. This is an example of （）.

判断题 Statistical independence means the outcome of one event is independent of the outcome of a second event.