Calculate the effective earth‚Äö√Ñ√¥s radius if the surface refractivity is 301.?

Calculate the effective earth‚Äö√Ñ√¥s radius if the surface

1.	Calculate the effective earth‚Äö√Ñ√¥s radius if the surface refractivity is 301.?
A.	8493 km
B.	8493 mmi
C.	6370 km
D.	6370 mi
Answer» B. 8493 mmi