The Dog Days Lawn Service advertises that it will completely maintain your lawn at an average cost per customer of $35 per month. Assume the costs are normally distributed. A random sample of 18 Dog...

The Dog Days Lawn Service advertises that it will completely maintain your lawn at an average cost per customer of $35 per month. Assume the costs are normally distributed. A random sample of 18 Dog Days customers shows the average cost to be $32.50 with a population standard deviation of $8.10. Do the data support the claim that the average cost per month is less than $35.00? Use a 5% level of significance. Show all steps.