Tabitha is a marketing consultant working with an advertising agency who has recently launched a radio and social media campaign for a new beverage product. the advertising agency is interested in determining the percent of people in the target market who have been exposed to the advertising message and can "recall" the message. tabitha recommends that a phone survey be utilized to contact individuals with mobile phones. tabitha works with the local mobile phone companies to determine the relevant prefixes or 3-digit numbers for individuals in the area and then instructs the research call center to randomly identify the remaining 4 numbers to ensure that all members of the population who have a mobile phone have an equal opportunity of being selected to participate in the study. tabitha is using the sample method.