IS THE SPEED OF LIGHT IN VACUUM EQUAL TO THE SPEED OF LIGHT IN AIR?

Hi,

For practical purpose and for calculations we take speed of light in vacuum and air to be same. The actual measurement shows that there is a difference in the speed of light. Here are the values given below

Speed of light in vacuum: 299,792,458 m/s

Speed of light in air: 298,925,574 m/s