Why does a rock become a metamorphic rock? A}because of magma hardening under the surface
B]because of great heat and pressure
C]because of time and compaction
D]because of lava hardening on the surface

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.

explanation:

the answer is a! (2.9 x 10^-18 j) hope i could someone. : )

explanation:

a