Sometimes when I listen to music, I feel the need to get up and dance. Sometimes the music is so good, I want a dance partner, and my cat, Gigi, is usually the only option. So, she and I will go bopping around the house. As you might imagine, Gigi is not the biggest fan of being bopped, and eventually decides to jump from my arms. Together we have about 150 kg of mass, and Gigi still has her 3.5 kg of mass. If my bopping speed is 0.5 m/s, and Gigi’s speed after pushing off from me is 2 m/s, what velocity do I have as I am thrown back by my cat (and her indifference to my bopping needs)?