Table 1 Balance Sheet, Income Statement, and Selected Market Data
Market value of common equity (market capitalization)	2,971,000,000
Book value of common equity (common equity on balance sheet)	870,000,000
Beta (5 year, raw)	1.22
Market value of preferred equity (total preferred from: Overviews>Capital Structure>Enterprise Value)	2,825,000,000
Book value of preferred equity (preferred stock (carrying value) from balance sheet)	N/A
Cost of preferred equity (weighted average YTW from Table 3 below)	7.19
Book value of debt (Notes/Bonds on balance sheet)	27,641,000,000
Market value of debt (sum of market values in Table 2 below)	173,986,280,000
Pre-tax cost of debt (weighted average of YTW on existing debt)	8%
Effective tax rate estimate (income taxes/EBT; EBT=EBIT-Interest Expense)	26%
Other needed data
3-month Treasury Bill Rate	24%

what is the weight of common equity using book values?