What color does grey and green make?

Answer 1

Sticking to the main English color terms the answer is probably just Green.

Grey is achromatic or neutral and Green is very distinctive and highly distinguished by our vision system. Adding grey to the green will change the green but not to the point that you would stop calling it Green. Unless you add enough grey to sufficiently small amount green then you would just cal that Grey. A cool grey. (as opposed to a warm grey.)

Answer 2

In the proper proportions, a variation of Teal.

Answer 3

Dark grey

Answer 4

Red