I need help with my chem homework

Question

Suppose a student places a beaker on his balance and does not tare it. Then, he adds three substances to the same beaker. The table shows the student's data before and after he adds each substance.

before and after
distilled water	56.700 g	71.550 g
sodium acetate	71.550 g	73.280 g
acetic acid	73.280 g	75.420 g

What is the mass of the beaker?

Answer 1

I'm not certain I understand the data table, but it appears that each substance was placed in the beaker sequentially. And I assume the "before and after" refers to the mass just before and just after the indicated substance was added. If this is true, the first line would be the empy beaker. It's mass is 56.700 grams.

Bob