Ok this question I was asked to calculate the mass of water with a syringe however when I take the average I have to round up to 10 because it was...

Ok this question I was asked to calculate the mass of water with a syringe however when I take the average I have to round up to 10 because it was really close to the volume of water given. Which the gives me a 0% error. Really confused am I doing something wrong? Also what measurements should I use for final answers?

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