Top: H i  surface density profile (inclination corrected), derived by ellipse averaging over the entire disk (dots) and over the approaching and receding sides separately (down-triangles and up-triangles, respectively). Middle: R-band surface brightness profile (from Papaderos et al. 2002). Bottom: “maximum disk” decomposition of the rotation curve. Dots and circles show the observed curve. Lines show the contributions of the gas, stars, and dark matter and the resulting rotation curve.