A student compared the chemical composition of soil in a certain area with the bed rock beneath it. She found that the chemical compositions were different. Which statement would best explain the difference in chemical composition? A. the soil layers were mature because a large amount of time had passed.

B. the soil is all that is left of a different kind of rock that weathered away.

C. The areas rain and extreme temperatures caused the soil to develop

D. the rainwater washed iron oxide from the A to the D horizon.

Why does bubbling occur when vinegar mixed with baking soda

What are the fixed alleles in the human species? o a. the alleles that are on the most chromosomes b. the alleles that change most often 000 c. the alleles that no one has d. the alleles that everyone has

Which statements best describe the differences or similarities between a comparative investigation and an experimental investigation? check all that apply. experimental investigations are best for showing cause-and-effect relationships, while comparative investigations do not necessarily show this type of relationship. comparative investigations are often impractical and unrealistic, while experimental investigations are the most practical and realistic kinds of investigations. comparative investigations allow for the use of a wide range of variables but do not have a control group, while experimental investigations involve variables that can be controlled. both experimental investigations and comparative investigations are designed to answer scientific questions. both experimental investigations and comparative investigations focus on making observations rather than collecting new data.