Most geologists believe that the dinosaurs became extinct 65 million years ago when a large comet or asteroid struck the earth, throwing up so much dust that the sun was blocked out for a period of many months. suppose an asteroid with a diameter of 5.0 km and a mass of 2.5×1014 kg hits the earth with an impact speed of 3.5×104 m/s . part a what is the earth's recoil speed after such a collision? assume that the mass of the earth is 5.98⋅1024 kg. (use a reference frame in which the earth was initially at rest.)