A team of researchers is investigating a new carbon-rich molecule important to life. They find evidence for the presence of a carbon-carbon double bond in the molecule. This observation means that the new molecule likely
exists as which of following?
A. an aliphatic hydrocarbon
B. a hydrocarbon ring
C. both cis and trans isomers

Hedgerows have created a new ecosystem within britain’s a. farms b. cities c. forests d. industrial areas

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.

What kinds of molecules can pass through the cell membrane without any problem?