1. The problem statement, all variables and given/known data You measure the mass of a physics textbook to be 2.97±0.07 kg, and use this value to estimate the total mass of 800 identical physics textbooks in the bookstore. What is the absolute uncertainty in your estimate of the total mass? I have been working on this for a while. I am not sure why I cannot get it. What I have tried is: 0.07(2)=0.014 -- since the uncertainty can go up or down .07kg then, multiplying the 0.014 by the 800 text books, to get 11.2kg. This however apparently is incorrect. What should I do?