First, solve for US Robotics Inc.$\text{'}$s unlevered beta.

Use US Robotics Inc.$\text{'}$s unlevered beta to solve for the firm's levered beta with the new capital structure.

Use US Robotics Inc.$\text{'}$s levered beta under the new capital structure, to solve for its cost of equity under the new capital structure.

What will the firm's weighted average cost of capital $($WACC$)$ be if it makes this change in its capital structure?

$7\mathrm{.}92\%$

$6\mathrm{.}93\%$

$7\mathrm{.}43\%$

$9\mathrm{.}90\%$