After bouncing around Philips, Atlantic, and Capitol playing Brazilian jazz or searching for an ideal blend of Brazilian and American pop, Sergio Mendes struck gold on his first try at A&M (then not much more than the home of Herb Alpert & the Tijuana Brass and the Baja Marimba Band). He came up with a marvelously sleek, sexy formula: dual American female voices singing in English and Portuguese over a nifty three-man bossa nova rhythm/vocal section and Mendes' distinctly jazz-oriented piano, performing tight, infectious arrangements of carefully chosen tunes from Brazil, the U.S., and the U.K. The hit was Jorge Ben's "Mas Que Nada," given a catchy, tight bossa nova arrangement with the voice of Lani Hall soaring above the swinging rhythm section…