Kim runs at a constant speed of 3 m/s for 5 s. She then stops to rest for 5 s. What is her average speed over the whole 10 s?

Which of the following best describes internal energy? a. the difference between the kinetic and potential energies of the particles in a system b. the sum of the kinetic and potential energies of the particles in a system c. the sum of the kinetic and thermal energies of the particles in a system d. the difference between the kinetic and thermal energies of the particles in a system