An average of RMB 77,000 is spent on each wedding, excluding the cost of the wedding ring and honeymoon, ___ China Wedding Industry Development Report． A．due to
According to some scientists，with the change in the world's________，dinosaurs died out but many smaller animals lived on. A．temperature B．climate C．weather
=
+
，则实数A=_____．
，再根据已知等式得出A、B的方程组，解之可得．
，
=
+
，
，
，