Waxy endosperm (wx), shrunken endosperm (sh), and yellow seedling (v) are encoded by three recessive genes in corn that are linked on chromosome 5.
A corn plant homozygous for all three recessive alleles is crossed with a plant homozygous for all the dominant alleles.
The resulting F1 are then crossed with a plant homozygous for the recessive alleles in a three-point testcross.
The progeny of the testcross are:
What is the genetic distance between Wx and V?