Measurements of midrapidity charged particle multiplicity distributions, \(dN_{\rm ch}/d\eta\), and midrapidity transverse-energy distributions, \(dE_T/d\eta\), are presented for a variety of collision systems and energies. Included are distributions for Au\(+\)Au collisions at \(\sqrt{s_{_{NN}}}=200\), 130, 62.4, 39, 27, 19.6, 14.5, and 7.7 GeV, Cu\(+\)Cu collisions at \(\sqrt{s_{_{NN}}}=200\) and 62.4 GeV, Cu\(+\)Au collisions at \(\sqrt{s_{_{NN}}}=200\) GeV, U\(+\)U collisions at \(\sqrt{s_{_{NN}}}=193\) GeV, \(d\)$+\(Au collisions at \)\sqrt{s_{_{NN}}}=200\( GeV, \)^{3}\(He\)+\(Au collisions at \)\sqrt{s_{_{NN}}}=200\( GeV, and \)p\[+\]p\( collisions at \)\sqrt{s_{_{NN}}}=200\( GeV. Centrality-dependent distributions at midrapidity are presented in terms of the number of nucleon participants, \)N_{\rm part}\(, and the number of constituent quark participants, \)N_{q{\rm p}}\(. For all \)A\[+\]A\( collisions down to \)\sqrt{s_{_{NN}}}=7.7\( GeV, it is observed that the midrapidity data are better described by scaling with \)N_{q{\rm p}}\( than scaling with \)N_{\rm part}\(. Also presented are estimates of the Bjorken energy density, \)\varepsilon_{\rm BJ}\(, and the ratio of \)dE_T/d\eta\( to \)dN_{\rm ch}/d\eta$, the latter of which is seen to be constant as a function of centrality for all systems.