Top panel: observed (solid lines) and synthetic (dashed lines) flux distributions along the major axis of the disk. The results are for model B, in which the inner (< 50 AU) and outer (> 50 AU) disks have different grain size distributions (see Sect. 5.2). For better representation, we only show the error bars of the observations which are larger than 5% of the fluxes. VLA 7 mm data are shown as black, band 3 as red, band 6 as green, and band 7 as blue lines. The VLA data at R> ~ 90 AU are not shown because of a low signal-to-noise ratio. Middle panel: the combined surface density profile of model B. Bottom panel: the vertical optical depth of as a function of radius at 7, 2.9, and 0.87 mm wavelength.