The ICU Admission dataset includes a variable indicating the age of the patient. Find and interpret 95% confidence intervals for mean age of ICU patients using the fact that, in the sample, the mean is 57.55 years and the standard error for such means is SE=1.42. The sample size of 200 is large enough to use a normal distribution.

20 TV remote controls were followed  over the years to find the mean lifespan of this model. The sample gave a mean of 7.2 years,  and the standard deviation of 0.6 years. The distribution of the population is unknown. Construct a 90% confidence interval for the mean lifespan of these remote controls.

A nutritionist wants to determine how much time nationally people spend eating and drinking. Suppose for a random sample of 1088 people age 15 or​ older, the mean amount of time spent eating or drinking per day is 1.74 hours with a standard deviation of 0.54 hour. Determine and interpret a 95% confidence interval for the mean amount of time Americans age 15 or older spend eating and drinking each day.

Find the critical t value to use in making an 80% confidence interval for a mean if the sample size is 35.  Write your answer with 3 decimal places.