If E. coli having heavy DNA was allowed to grow for 80 minutes on a medium containing 14NH4Cl then what would be the proportions of light and hybrid densities DNA molecule?

80minutes= 80/20= 4 generationsInitially DNA contain 15N15NThen it is placed in a medium containing 14N for 3 generation.After 1st generation:15N15N→ 15N14N    15N14N (2 Hybrid DNA molecules)After 2nd generation15N14N    15N14N → 15N14N    14N14N   15N14N    14N14N (2 light DNA and 2 Hybrid DNA molecules)After 3rd generation:15N14N    14N14N   15N14N    14N14N → 15N14N    14N14N   14N14N   14N14N 15N14N    14N14N   14N14N   14N14N (6 light DNA and 2 hybrid DNA molecules)After 4th generation2(15N14N) → 2 (15N14N    14N14N)6(14N14N) → 6 (14N14N   14N14N)Total no. of light DNA= 14Total no. of Hybrid DNA= 2% of light DNA= 87.5%% of light DNA= 12.5%