A researcher is designing an experiment to determine whether the production of amylase increases when a person anticipates eating starchy food. She measures the amount of amylase in the saliva of 10 volunteers who are offered a bowl of pasta and of 10 other volunteers who are offered a bowl of scrambled eggs. In analyzing her data, she finds some variation in the amount of amylase among the samples within each group, but no significant difference in the amount of amylase between the two groups. She concludes that she needs to revise her experimental design and try her experiment again. What would be the best thing she could do to improve her experiment?

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.