Glucose is a compound made from three elements: carbon, oxygen, and hydrogen. For glucose to be broken down into these elements, it must undergo . A. filtration or distillation
B. an irreversible physical change, such as tearing or slicing
C. a reversible physical change, such as boiling or melting
D. a chemical change

in cartography, a contour line (often just called a "contour") joins points of equal elevation (height) above a given level, such as mean sea level. a contour map is a map illustrated with contour lines, for example a topographic map, which thus shows valleys and hills, and the steepness or gentleness of slopes.

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can you list the answers so i can answer