7. Which of the following situations is most appropriate for using t-distribution to construct a c onfidence interval? a. The population variance is known, the sample size is small with lognormal distribution. b. The population variance is known, the sample size is large with normal distribution. c. The population variance is unknown, the sample size is small with normal distribution. Aomolo onointing of 25 oboroticno inolooted from anonulation with variono of 1 70