The fourth issue of the HCMR, Vol. 2 No. 2, is now available online and in print! This issue includes a diverse body of articles, such as "Arrow's Impossibility Theorem: Two Simple Single-Profile Versions" by Prof. Allan M. Feldman (Brown University) and Prof. Roberto Serrano (Brown University), "Young Tableaux and the Representations of the Symmetric Group" by Yufei Zhao (Massachusetts Institute of Technology '10), and "The Congruent Number Problem" by Prof. Keith Conrad (University of Connecticut). View Vol. 2 No. 2 to find our standard complement of articles, features, problems, and solutions.