The total market value is 6800. (sh cap 425 x 4 (25c shares) x $4 (mkt value per share).
Property is 2297 (land & buildings) + 165 (billing under construction) = 2462 (Retail is the difference).
0.625 is the asset beta of property. This is calculated by ungearing the equity beta of ‘representative portfolio of commercial property companies’ using their gearing rato of 50:50. Using the asset beta formula.