Answer:
Quantitative RT-PCR;
PCR,
RT-PCR
Explanation:
Abby wants to determine changes in gene expression levels in a tissue, so she uses quantitative RT PCR to measure the quantitative expression of gene and amount at certain time and conditions
Bob is trying to extract genetic information from a wooly mammoth fossil, so he uses PCR which will help to isolate and amplify the specific gene of interest and regions for further study instead of whole genomic DNA.
Chris needs to express a gene in bacteria that matches the form expressed in kidney cells, so she uses RT-PCR to study the gene expression and to distinguish the exons and introns which will help to study the diagnosis of particular disease.