Section 6.1: Precision, Accuracy, and Estimation
Links

A Dictionary of Units of Measurement
This is a good reference site.
http://www.unc.edu/~rowlett/units/index.html

The International System of Units (SI) This is an excellent reference site dealing with the metric system.
http://www.unc.edu/~rowlett/units/sipm.html

Accuracy and Precision These are excellent sites that seeks to answer the question asked in Problem 1.
http://www.flatsurv.com/accuprec.htm

Error, Accuracy, and Precision
http://elchem.kaist.ac.kr/vt/chem-ed/data/acc-prec.htm