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If a company with a rating of BBB has on issue debentures paying a coupon rate of 6% pa and the market yield on similar BBB securities is 7% pa, what is the correct cost of debenture capital ( kdb ), before tax, that the company should use when estimating the WACC using the textbook WACC formula? The riskfree rate is 5% pa.and the Rm is 13%pa. 5% 6% 10% 7% 13% None of the other given options is correct