<prompt> Incomplete casting can be due to:Insufficient venting.Inadequate or too small spreu.Low casting pressure.All of the above.  <response>: Reasons for incomplete castings:Insufficient ventingInadequate sprue too small sprueInsufficient alloy usedAlloy not sufficiently molten or fluidMold is not heated to casting temperaturePremature solidification of alloyLow casting pressure 