Answer: If more than one variable is changed in an experiment, scientist cannot attribute the changes or differences in the results to one cause. By looking at and changing one variable at a time, the results can be directly attributed to the independent variable.
Metallurgy is the science and technology of metals and alloys. The study of metallurgy can be divided into three general groups: ... Process metallurgy is concerned with the extraction of metals from their ores and the refining of metals.
Answer:
Catalysts
Explanation:
Catalysts lower the aviation energy.
Molecular clocks because the m<span>easure changes in DNA or proteins to indicate degrees of relationship among species.Molecular clocks, together with evidence from the fossil record, allows scientists to estimate how long ago various groups of organisms diverged evolutionarily from one another</span>
