1. Tracy and Eric are timing how fast marbles roll down an inclined plane. They plan to do this 5 times, and then take the average time for their results. What would be the BEST way to improve the accuracy of
their data?

A. Include marbles of three different colors in their investigation
B. Include the average of 20 trials down the inclined plane
C. Use marbles of 10 different densities
D. Use toy cars instead of marbles

What pattern of migration do whales follow?

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.

Which of the following requires the use of energy and the of transport proteins to move a molecule across a cell membrane?