In a series of two-point mapping crosses involving five genes located on chromosome II in Drosophila, the following recombinant (single-crossover) frequencies were observed: pr–adp 29% pr–vg 13 pr–c 21 pr–b 6 adp–b 35 adp–c 8 adp–vg. 16 vg–b. 19 vg–c 8 c–b. 27 Given that the adp gene is near the end of chromosome II (locus 83), construct a map of these genes.