What percentage is this of the earths speed around the sun ? Assume that the orbit of the earth is a circle with the radius of 1.5x10^11 m Vrecoil = 1.7x10^-6 m/s

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 2.5x1014 kg hits the earth with an impact speed of 4.0x104 m/s . Part A