B
Think of inertia of getting into a car accident without a seat belt although the car stops you will not you would likely fly out the window
We Know,
K.E. = 1/2 mv²
480 = 1/2 (m)(8)²
m = 960/64
m = 15 Kg
So, the mass of the object is 15 Kg
Precisely around 1,800 miles below.