An average-sized asteroid located 8 x 10^7 km from Earth's centre with mass 2.5 x 10^13 kg is detected headed directly toward Earth with a speed of 1.6 km/s. What will its speed be (in km/s) just before it hits our atmosphere? (You may ignore the size of the asteroid: Assume the height of our atmosphere is 110 km, the radius of the Earth is 6.38 x 10^6 m, and the mass of the Earth is 5.97 x 10^24 kg.) km/s