The Canadian dollar weakened against the greenback on Tuesday, and the yield on benchmark government debt slipped. The loonie was trading 0.1% lower at C$1.3731 to the greenback, or 72.83 U.S. cents, after trading in a range of 1.3711 to 1.3756. Canadian government 10-year bond yields fell 3.7 basis points to 3.279%. The yield on similar U.S. government benchmark debt fell to 4.2517%. U.S. July crude futures rose 4 cents to $80.37 a barrel on Tuesday.