[单选题]
You (50-kg mass) skate on ice at 4.0 m/s to greet yom(1phs9whyw . ur fru, no uo4bm6s+3e bmi8x/vbo-iend (40-kg mass), who is standing still, with 6n s-+u4/3o,be 8movmo xibub open arms. As you collide, while holding each other, with what speed do you both move off together?
