Please help me solve this problem step by step. I need to prepare for the exam. Thank you.

In order to estimate the difference between the average yearly incomes of marketing managers in the East and West of the United States, the following information was gathered. Degrees of freedom = 83.

East n₁= 40, Mean= 72 (in $1000), s₁= 6 (in $1000)

West n₂= 45, Mean = 78 (in $1000), s₂= 8 (in $1000

At= .05, test to determine if the average yearly income of marketing managers in the East is significantly different from those in the West.

State the null and alternative hypothesis, critical value, test-statistic, and your decision.