What is the process that changes one set of chemicals into another set of chemicals?

indicate valleys, hills, steepness and gentleness of slopes.

explanation:

contour lines on a map indicate elevation, or depth. numeric notations on contour lines refer to the level of elevation, or height about sea level.

metric time was an attempt to create a standard unit of time based off of 10, but it never took off an is not included in the metric system (si)