Polymerase chain reaction (pcr) is an essential technique for the study of dna. pcr uses a dna polymerase enzyme from thermophilus aquaticus to amplify dna extracted from any sample. in order for the reaction to work, researchers must transfer microliters of sample to the reaction vessel for pcr. if a researcher has a dna sample with a concentration of 0.28 micrograms per microliter, how many microliters of dna must be transfered to conduct a 50 microliter reaction if the final concentration should be 2.2 nanograms per microliter?