The amount of pollutants that are found in waterways near large cities is normally distributed with mean 9.8 ppm and standard deviation 1.5 ppm. 16 randomly selected large cities are studied. Round all answers to 4 decimal places where possible.

1. What is the probability that one randomly selected city's waterway will have more than 9.7 ppm pollutants?
2. For the 16 cities, find the probability that the average amount of pollutants is more than 9.7 ppm.
3. Find the IQR for the average of 16 cities.

Q1 =

Q3 =

IQR:

please note for no 2 i got 0.6064 as my answer and it marked me wrong please explain step by step

also for Q3 i got 10.055 and it marked me wrong. please explain step by step

Thank explain