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Often on a topographic map, every fifth contour line is darkened. what is this line called? a. key b.slope c.benchmark d. index contour

Freezing and boiling are endothermic processes. this means that these processes absorb energy from their surroundings in order to occur. use this information and the data you collected in the phase change gizmo to describe what happens to the temperature of water when you boil it, then explain why this result occurs.

Which type of intermolecular attractions holds ammonia molecules together with other ammonia molecules?