Figure 2: melting and boiling points of some substances
substance melting point boiling point
hydrogen
-259.3°c
-252.9°c
nitrogen
-210.0°c
-195.8°c
acetic acid
16.6°c
117.9°c
gold
1064.2°c
2856°c
26. based on the information in figure 2, which substances would be liquids, solids, and gases at 0°c?

Over the past 60 years, many amphibian species have experienced significant population declines and some species have become extinct. scientists suspected that local human activities such as the destruction of wetlands, regional pollution, and deforestation were the main reasons for these losses. however, research over the past 20 years reveals significant amphibian population declines in protected areas of the world, such as nature preserves and parks. these global declines suggest widespread problems including increased ultraviolet radiation, acid rain, and disease. in switzerland, for example, 14 of the 20 native amphibian species are threatened with extinction. chytridiomycosis is a fungal disease first identified in 1998 as a cause of massive amphibian deaths. in some severely impacted populations, a few individuals have survived, perhaps because of some natural resistance. if these resistant individuals continue to survive and prosper, new resistant populations might emerge. this would be an example of the founder effect artificial selection genetic drift natural selection sexual selection

What do all macromolecules have in common with each other? oa. they all are formed from the same elements. ob. they all have major roles in cell membranesoc. they all act as catalysts in the body. od. they all have peptide bonds between carbon atoms.

Which best describes a gene? a. a sister chromatid b. a chromosome c. a tetrad d. a piece of a chromosome