A:Answer Hi Vic.
The required distance depends on what type of cooking surface is on the range as well as building codes. The link below is from the GE website for appliance clearances and states that if it is installed over an electric, induction or gas range, the distance between the top of the range and the bottom of the microwave/hood should be between 13" - 16". The unit can NOT be installed over any cooking surface with a combined burner output above 60,000 BTUs.
Hope this helps.
JimmyC
https://products.geappliances.com/appliance/gea-support-search-content?contentId=21841