Measurement and Data: Drawing Scaled Graphs to Represent and Compare Data (CCSS.3.MD.2)

Subtract the volumes in the same unit: 2000 mL − 750 mL = 1250 mL. 1750 mL adds instead of subtracts, 250 mL subtracts incorrectly, and 1250 liters uses the wrong unit.

A textbook is about 800–1500 grams (around 1 kilogram). 8 g or 80 g are far too light, and 80 kg is about the mass of an adult, which is unrealistic for a book.