These issues present challenges for regional urban areas. housing availability inadequate services pollution reduced population rural migration

These issues present challenges for regional urban areas: housing availability, pollution and rural migration. Housing availability is one, because there are many people looking for housing in those areas, pollution because urban centers often have industrial sites where toxic fumes are released into the air, as well as transportation pollution and rural migration, because people from rural areas come to urban areas often to look for jobs.

Answer// dinosaurs emerged during mesozoic era;

Magma forms by partial melting of upper mantle and crust. partial melt means that only a fraction of the available material forms a melt, and that the remainder stays solid. the partial melt rises because of its lower density and ascends through he crust. this is so conclusive mean the answer would be magma igneous rocks or balistic magma.