The electromagnetic waves with the longest wavelengths and the lowest frequencies are

Waves with the longest wavelengths have the lowest frequencies. Waves with the shortest wavelengths have the highest frequencies. Electromagnetic waves in the spectrum range from very long wavelength, low frequency radio waves to very short wavelength high frequency gamma rays.

Urban growth invariably feeds increased commercialization and industrialization. it requires continually expanding land areas. when urbanization rates are high, and countries do not have the institutional and managerial capacities or economic wherewithal to manage such rapid growths, they exert intense pressure on the types and nature of the resulting settlements. they contribute to the development of overcrowded slums and shanty towns without adequate essential services and necessary infrastructure.-by asit k. biswas and cecilia tortajada