You measure 44 textbook's weights, and find they have a mean weight of 81 ounces. Assume the population standard deviation is 3.8 ounces. Based on this, construct a 95% confidence interval for the true population mean textbook weight. Round your answer to 2 decimals

For each case below, state what type of statistical test you would use to analyze each dataset. Explain your answer! Hemoglobin is a protein responsible for carrying oxygen throughout your blood stream. Blood hemoglobin levels in humans average at about 14.5g/dL. We are interested in whether a sample of 20 iron deficient individuals have lower blood hemoglobin levels compared to the general population. The average hemoglobin level for our sample is 10.9g/dL, with an estimated population standard deviation of 1.92g/dL. A researcher is looking at whether the time it takes for rats to relearn how to run a maze decreases after they’ve been exposed to the maze more than once. Using 15 rats, he measures how quickly they are able to successfully run a maze at two different times points: once when they are first exposed to the maze, and again after they’ve run the maze three times.  A social psychologist is curious about whether social rejection increases aggression in narcissists. He…

A particular fruit's weights are normally distributed, with a mean of 747 grams and a standard deviation of 8 grams. The heaviest 13% of fruits weigh more than how many grams? Give your answer to the nearest gram.

A particular fruit's weights are normally distributed, with a mean of 380 grams and a standard deviation of 12 grams.The heaviest 9% of fruits weigh more than how many grams?Give your answer to the nearest gram.