Tropical Tous is considering an expansion of its operations, which will require the company to issue new debg and equity. Tropical's investment banker provided the following information about the cost of issuing new debt.

Amount of Debt Issued: Yield to Maturity rd

$1 - $450,000 4.5%

$450,001 - $750,000 5.8%

Over $750,000 6.5%

If Tropical's capital struture consists of 60 percent debt, what WACC break points are associated with issuing new deby