. A researcher studies the evolutionary relationships between influenza viruses by comparing the genomic sequences of the viruses found in pigs, ducks, and humans in a given year. When evaluating the viruses that had infected these hosts the previous year, she identifies a cross-species transfer from humans to pigs. This information supports the hypothesis that cross-species transfer leads to more severe disease if during the previous year suffered a severe influenza pandemic.

Two students are working together on an experiment that measures the effect of different liquid fertilizers on the thickness of plants’ stems. which is most likely to result in the greatest amount of error in their scientific experiment? a.one student measures the plant stem widths by using calipers. the other student measures the widths of the same plant stems again by using a different pair of calipers. b.one student measures the plant stem widths by using calipers. the other student types the measurements as they are taken into a computer spreadsheet. c.one student weighs liquids for the experiment by using a calibrated scale. the other student weighs liquids for the experiment by using a different calibrated scale.