Hello, new to n scale working on track design.  Which turnouts do I need to move from various radius size ovals?  I can't find any info for this.
Which turnouts from 9.75 to 11.25
    ".                ".     11.25 to 12.5
    ".                ".     12.5. To 14
    ".                ".     14 to 15.5
    ".                ".     15.5 to 17.5

Also is track radius measured from center of track to center?

Any and all help is appreciated! Chris