Mr. Stewart bought a new battery for his car. The battery cost $72. Since batteries are a taxable item, he had to pay a sales tax of 7.5%. What was the total cost of the battery in dollars and cents? Mr. Stewart spent $77.40 on his new car battery.

Atextile fiber manufacturer is investigating a new drapery yarn, which the company claims has a mean thread elongation of 12 kilograms with a standard deviation of 0.5 kilograms. the company wishes to test the hypothesis upper h subscript 0 baseline colon mu equals 12 against upper h subscript 1 baseline colon mu less-than 12 using a random sample of n equals 4 specimens. calculate the p-value if the observed statistic is x overbar equals 11.8. round your final answer to five decimal places (e. g. 98.76543).