Researchers in the Suess group at MIT are studying the properties of iron sulfur clusters in biology. In biology, 4 iron, 4 sulfur clusters are arranged in a cube structure. By name or number, identify all of the following three statements which are true of 4 iron, 4 sulfur clusters: 1) The iron centers are low spin 2) Increased amount of hydrogen bonding to the sulfur atoms from amino acid residues increases the potential of the active redox couple 3) The oxidation state of sulfur in these clusters is 0