What is the exact value of the circumference of the circle whose radius is 8.5ft

Can someone me with this? i’m not sure what to put for my equations.

What is not a question to ask to determine the reasonability of a solution

The weights of soy patties sold by a diner are normally distributed. a random sample of 15 patties yields a mean weight of 3.8 ounces with a sample standard deviation of 0.5 ounces. at the 0.05 level of significance, perform a hypothesis test to see if the true mean weight is < 4 ounces. what is the correct conclusion at the 0.05 level of significance?