It is ;
sub sonic - less than mach 1
transonic -mach 1(actually between 0,95-1,1 mach)
Supersonic - above mach 1 and less than hypersonic ones which is above mach5+
When you check the picture , it says 0,2/0,3-4 mach!!
I can not distinguish 0,2 or 0,3 but it should be 0,3 I guess .
The test...