Standard 1:2:3 and 1:2:4 batching ratios by volume for 3000 PSI to 4000 PSI concrete mixes.
Complete ASTM rebar diameter specifications (#3 through #18) and weight per linear foot.
Nominal vs. actual dimensions for framing lumber (2x4, 2x6, 4x4, 2x10) and board foot quick lookup.