GEOLOGY

Detailed explanation-1: -Landslides: occur when gravity quickly pulls rock and dirt downhill. Floods: a great flow of water over an area that is usually dry land. through which steam, lava and ashes erupt. Cause both destructive and constructive changes to landforms.

Detailed explanation-2: -Common constructive and destructive forces include volcanoes, erosion, weathering and deposition, and many others.

Detailed explanation-3: -Geologists and volcanologists, a type of geologist specializing in volcanoes, conclude that volcanoes are constructive forces because they often create new landforms and build on existing ones.

Detailed explanation-4: -Collection and analysis of data indicates that constructive forces include crustal deformation, faulting, volcanic eruption and deposition of sediment, while destructive forces include weathering and erosion.