1. The problem statement, all variables and given/known data A magnetic-field technique for stabilizing a He-Ne laser to 2 parts in 10^10 has been patented. At 632.8 nm, what would be the coherence length of a laser with such frquency stability. 2. Relevant equations Coherence time =1/delta frequency coherence length = c/delta frquency 3. The attempt at a solution dont know what 10^10 stands for and how to solve this help would be much appreciated.