Which of the following rules should you follow to balance chemical equations?
оа
change the subscripts and add coefficients
change the molecular formulas
add coefficients as needed
change only the subscripts
oc
d

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:

they are all solids.