Due to burning of fossil fuels such as coal and petroleum, the level of carbon dioxide (CO2) in the atmosphere has been increasing for more than 150 years. Should this increase tend to accelerate or slow down the rate of chemical weathering of Earth’s surface rocks? Explain how you arrived at your conclusion.

Dwarf galaxies are select one: a. relatively rare. b. not very bright c. mostly spiral shaped. d. none of these.

1. variations in a population of moths allow for some of its members to be able to adapt to environmental changes. the better adapted of the moths will be able to survive the change and thus prevail as the “fittest” of the species. (a) describe three mechanisms in which variation can occur within a species population. (b) explain which mechanism or mechanisms would be responsible for the survival of a population of peppered moths better than white moths in an environment affected by industrial soot. justify your answer.

Cathy hypothesized that corn would not grow in mud. to test this hypothesis, she took corn kernels and placed 5 in mud, 3 in soil, and 2 in water. to her surprise, the kernels in the mud grew faster than the kernels in the soil. what error might have caused these unexpected results? a. wrong hypothesis b. not enough variables c. undefined control d. too many variables