A modern high-speed passenger train travels at a cruising speed of 300 km h-1 on a level track. What is a reasonable estimate of its kinetic energy at this speed?
107 J10^7\text{ J}107 J
109 J10^9\text{ J}109 J
1011 J10^{11}\text{ J}1011 J
1013 J10^{13}\text{ J}1013 J