by Michael Freedberg 　　Donna Summer's brassy, matter-of-fact mezzo does not play the sexy sanctified diva, and her musicians' crisp, loud beats don't evoke rapture or delirium. Instead, she and her rhythm men live up to the title of "She Works Hard for the Money." Here's praise for a waitress' 12-hour workday that sums up Summer's own post-dance queen job status, as well as disco fans' own spotlighted lives and maintains the pressure, from the steel-and-synth riffs of "Stop, Look & Listen" to the impatient tenderness of "People, People." No one writes about love with as mesmeric a sense of wonder as Summer confesses in "Love Has a Mind of Its Own," "Unconditional Love," and "I Do Believe (I Fell in Love)."