27. tires that are piled, stacked or dumped illegally may lead to all of the following, except: a) dangerous burn areas that, once ignited, emit dangerous toxic fumes and are nearly impossible to put out b) an overabundance of obstacle course challenges c) retained water that is a breeding ground for mosquitoes d) accelerated breeding of mice and rats

A. describe the model of urban structure most often observed in mega-cities in developing countries. explain how this model differs from common urban structures in north america. b. describe at least two factors leading to the growth of mega-cities in developing or least-developed countries. c. identify and explain two factors that led to the formation of squatter settlements in mega-cities in developing countries.