Why does rock salt make ice cream freeze but makes ice on the road melt?

Question

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Answer 1

The rock salt pulls heat out of the ice. Thus lowering the temperature of the water/ice mix and will cause the ice cream to freeze since it is now surounded by a water/ice mix that is below 32 degrees F.

Now why does it melt the ice on the road.  The salt lowers the freezing temperature of water, and lowering the freezing temperature makes it melt as long as the outside temperature is above the new freezing temperature.