Greshak Corp. is attempting to estimate its optimal capital structure. Currently, the company's cost of equity, which is based on the CAPM, is 12.0% and the risk free rate and equity market risk premium are 4.0% and 6.0%, respectively. Outside analysts inform Greshak's management team that the company's most optimal capital structure would have a mix of 40% debt and 60% equity. Assuming the company's current capital structure consists of 20% debt and 80% equity, and its tax rate is 35%, what must Greshak Corp.'s unlevered beta be?