Extrude from a face

Heres another guys.  After I did a thin extrusion from a face of a previous extrusion and into the base of my cavity, the graphics are showing a line where there should be none.  It looks as if the heights of the start of the thin feature and the face from where I extruded from are at different heights.  This should not be.  Also, I thought I hade the nack of using the measuring tool.  I tried to measure from the top face of the thin extrusion to the top face of the previous rib I extruded and I cannot see any readout or measurement.  Any help with either or both would be greatly appreciated.

Thank you again.

Sid

SolidworksParts And Features