A system consists of a 5.00-kg object moving down along the y-axis at a speed of 25.0 m/s, as well as an 8.00-kg object . The system has a net momentum of 35 kg∙m/s in the direction of the +y axis. What is the velocity of the 8.00-kg object? Express the direction of its velocity as a counterclockwise angle to the +x-axis.