Answer:
16 pg at the end of S
16 pg at the end of G2
Step-by-step explanation:
A cell has 8 pg of DNA per nucleus in G1.
During S phase the DNA replicates, so every nucleus will contain double the normal amount of DNA that was present in G1. Therefore, at the end of S each nucleus would have 16 pg of DNA.
During G2 the cell continues growing and preparing for mitosis, but DNA content does not change: there are still 16 pg per nucleus.