The authors of the paper "Deception and Design: The Impact of Communication Technology on Lying Behavior"+ asked 30 students in an upper division communications course at a large university to keep a journal for 7 days, recording each social interaction and whether or not they told any lies during that interaction. A lie was defined as "any time you intentionally try to mislead someone." The paper reported that the mean number of lies per day for the 30 students was 1.58 and the standard deviation of number of lies per day was 1.02. (a) What assumption must be made in order for the t confidence interval of this section to be an appropriate method for estimating μ, the mean number of lies per day for all students at this university? We need to assume that the 30 students formed a random sample of all students in the communications department. We need to assume that the 30 students formed a random sample of all students in the course. We need to assume that the 30 students told the truth about the number of lies they told. ◇ We need to assume that the 30 students formed a random sample of all students at this university. ○ We need to assume that the 30 students formed a random sample of all students in the country. (b) Would you recommend using the t confidence interval to construct an estimate of μ as defined in part (a)? Explain why or why not. ◇ Yes, it is very likely that the 30 students from the upper division communications course are representative of students in the communications department, so the assumption of randomness is valid, and the t confidence interval can be used. Yes, it is very unlikely that the 30 students from the upper division communications course are representative of all students in the course, so the assumption of randomness is valid, and the t confidence interval can be used. No, it is very unlikely that the 30 students from the upper division communications course are representative of all students at the university, so the assumption of randomness is not valid, and the t confidence interval should not be used. ◇ Yes, it is very likely that the 30 students from the upper division communications course are representative of all students in the country, so the assumption of randomness is valid, and the t confidence interval can be used. ◇ No, it is very unlikely that the 30 students from the upper division communications course told the truth about the number of lies they told, so the assumption of randomness is not valid, and the t confidence interval should not be used.