PLS look at the picture below and explain or calculate how the numbers in the denominator and numerator were gotten

Example 13.5 Mean time between collisions Estimate the mean time between collisions for a nitrogen molecule at 1.0 atm pressure and room temperature (20C). PREPARE Because vrmS is essentially the average molecular speed, the mean time between collisions is simply the time needed to travel distance A, the mean free path, at speed vrms. SOLVE We found A = 2.3 x 107 m in Example 13.1 IE' and vIms = 509 m/s above. Thus the mean time between collisions is ,1 2.3 x 10-7 m At = = = 4.5 x 1010 ( )avg vms 509 m/s 5