A company with a 25% tax rate buys preferred stock in another company. The preferred stock has a before-tax yield of 7.00%. Assume a 70% dividend exclusion for tax on dividends. What is the preferred stocks after-tax return? (Round your final answer to two decimal places.)

Please explain with formula as I'm trying ton understand it.

After-tax dividend yield = Preferred dividend rate [1 (1 Div exclusion%)(T)]