Explain why and how theories may be changed or replaced over time.

Answer and Explanation: This is true that theories do change or get replaced overtime. We all know that in any scientific investigation the scientist put forth the theories which are basically the ideas explaining something particular. We also know that the world is experiencing constant changes and those changes could be of Technology or of overall world order so, whenever a scientist gives us the theory, that theory is made according to the situations and environment of that particular time and in future with the passage of time and with the advancement of Technology and other variables, scientist do need to re-evaluate theories. They either make some positive changes keeping in view the changing circumstances of the current situation or discard the theory altogether depending on its nature. The name research itself indicate that scientists research the already searched idea and in that way the New theory which comes after the modification of old theory or altogether the new theory takes place of the old one.

Sample Response: Theories may be changed over time as new information is discovered or new technologies are developed. New developments lead to changes in experimental methods, which provide information that may or may not support the existing theory. If the theory is still supported, it may be updated. If it is not supported, but the results are true and relevant, the theory may be replaced

Explanation:

answer:

convection currents in the magma drive plate tectonics. heat generated from the radioactive decay of elements deep in the interior of the earth creates magma (molten rock) in the aesthenosphere. the aesthenosphere (70 ~ 250 km) is part of the mantle, the middle sphere of the earth that extends to 2900 km.