The average life expectancy of tires produced by the whitney tire company has been 40,000 miles. management believes that due to a new production process, the life expectancy of their tires has increased. in order to test the validity of their belief, the correct set of hypotheses is a. h0: μ > 40,000 ha: μ ≤ 40,000. b. h0: μ ≥ 40,000 ha: μ < 40,000. c. h0: μ < 40,000 ha: μ ≥ 40,000. d. h0: μ ≤ 40,000 ha: μ > 40,000.