In statistical surveys where individuals are randomly chosen and asked questions, experience has shown that only 22% of those under 25 years of age, and 66% of those aged 25 to 50 will respond, and 12% of those over the age of 50 will not respond. Asociologist is to send a questionnaire to a group of people, of which: 30% are younger than 25 years of age, 31% are over the age of 50, the remainder are between the ages of 25 and 50 years of age. a) What will be the non-response rate here? That is, what percentage of all questionnaires distributed will not be responded to? b) If a questionnaire is responded to, what is the probability that the respondent is over the age of 50