Multi-configuration Hartree-Fock expectation values of the inner < r(<)> and outer < r(>)> electron radii and the interelectronic angle are reported for the ground and 54 singly-excited states of helium. These mean values can be visualized as defining a nearly right-angled triangle. Expressions connecting these expectation values with the mean value of the interelectronic distance < r(12)> are found to be quite accurate. Some observations are made on singlet-triplet differences of . (C) 2011 Elsevier B.V. All rights reserved.