(c) Estimate the proportion of those who think they have worked beyond a safe limit. Your answer to this question should refer to the whole population and not to any particular group. (d) Estimate the variance of the estimator in (c). You may ignore the finite population correction in your answer. (e) Do anesthesiologists differ significantly from residents in this matter? 1. Are anesthesiologists overworked and therefore putting patients at risk? This question was investigated as part of a survey carried out at the University of Florida. The population of those practicing anethesiol- ogy was stratified into three groups: anethesiologists (composing approx- imately 70% of the population), anesthesiology residents (composing ap- proximately 10% of the population) and nurse anesthetists (composing approximating 20% of the population). The frequencies of those in each stratum who thought they had worked without a break beyond a safe limit sometime during the last 6 months are shown in the accompanying table: Frequency Percentage Job classification Beyond safe limit Anesthesiologist No 417 31.4 Yes 913 68.6 Anesthesiology resident No 29 17.6 Yes 136 82.4 Nurse anesthetist No 240 21.8 Yes 860 78.2