The genes kn-1 (produces leaves with small "knots") and d3 (causes dwarfed stature) are 40 map units apart on chromosome 1 of corn. the distance between these two loci was determined using a corn line with no known inversions on chromosome 1. a paracentric inversion of 20 map units lies between (but not containing) kn-1 and d3 in popcorn lines. if the distance between the two loci was mapped using a heterozygote with one normal chromosome 1 and one paracentric inversion chromosome 1, what is the apparent distance between the two loci?