The boundary between cold and warm air masses is called a?...

With cold fronts and warm fronts, the air mass at the leading edge of the front gives the front its name. ... When two air masses meet together, the boundary between the two is called a weather front. At a front, the two air masses have different densities, based on temperature, and do not easily mix.

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yes peace and development are complementary to each other since they both undergo a great deal of getting where they want to go whether its peace in general and. development