From her firm's computer telephone log, an executive found that the mean length of 68 telephone calls during July was 4.85 minutes with a standard deviation of 5.03 minutes. She vowed to make an effort to reduce the length of calls. The August phone log showed 47 telephone calls whose mean was 2.932 minutes with a standard deviation of 2.612 minutes.

(a) Choose the appropriate hypotheses for a right-tailed test. Assume ₁ is the average call length in July and ₂ is the average call length in August. a. H₀: ₁ - ₂ 0 vs. H₁: ₁ - ₂ > 0 b. H₀: ₁ - ₂ < 0 vs. H₁: ₁ - ₂ 0

(b-1) Obtain a test statistic t_calc and p-value assuming unequal variances.(Use the quick rule to determine degrees of freedom. Round your answers to 3 decimal places.)