Estimation Station 2 - How many cups filled just to that level will it take to empty the 2L of Coke?

Lots of discussion at this station.  People looked at the bag of cups for the 16 fluid oz size.  They asked if we poured out the one cup from this 2 Liter.  Yes, we did.  We filled it to the first indent on the plastic cup.  They would use their fingers to measure how much was missing on the Coke bottle to the plastic cup. 

How many cups do you think?