The accompanying diagram shows resistivity (reciprocal of conductivity) data for four soli...

The accompanying diagram shows resistivity (reciprocal of conductivity) data for four solid materials from 77 K to 273 K, scaled so that the maximum value plotted for each material is 1. Two are metals, one of which undergoes a transition between ordered and disordered spins in this temperature range, Speculate as to which plots correspond to these two metals and what the other two materials might be. Explain your reasoning.