I just need help with number 3 - please include the excel formula

1. Calculate total cost of conference for each employee 2. Create nested IF functions in Column G, cell G2 through G17 meeting the following criteria: A. If Total expense is less than or equal to $3000, the office will cover the full cost B. If Total expense is more than $3000, but less than or equal to $5000, the office will cover 50 o C. If Total expense is more than $5000. the office will cover 25%