Shadow Corp. has no debt but can borrow at $7\mathrm{.}6$ percent. The firm$$s WACC is currently $9\mathrm{.}4$ percent, and the tax rate is $25$ percent.$(1)$ If the firm converts to $25\%$ debt what will the company's WACC be$?(2)$ If the firm coverts to $50\%$ debt what will the company's WACC be$?$