Draw all of the resonance structures for the resorufin anion that satisfy the octet rule (that is, no carbocations). In each resonance structure, identify any ringsthat are nonaromatic as a result of cross-conjugation.

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.

there is none because earth is stationary and flat.