Find, by opening the records, the yield strengths of copper, brass (a solid solution of zinc in copper) and bronze (a solid solution of tin in copper). Report the mean values of the ranges that appear...

Find, by opening the records, the yield strengths of copper, brass (a solid solution of zinc in copper) and bronze (a solid solution of tin in copper). Report the mean values of the ranges that appear in the records. What explains the range within each record, since the composition is not a variable? What explains the differences in the mean values, when composition is a variable?