A skier travels from the base of a ski slope to the summit and increases her gravitational potential energy by $10\,000\,\text{J}$. She then goes back down the slope. When she reaches the bottom, her kinetic energy is $2000\,\text{J}$. How much energy is dissipated in overcoming friction and air resistance during the descent?
- A$2000\,\text{J}$
- B$8000\,\text{J}$
- C$10\,000\,\text{J}$
- D$12\,000\,\text{J}$