What type of succession will follow if jones high school was to be abandoned for 20 years due to a serious storm? state why?

Primary succession would occur. The buildings would slowly collapse, effectively meaning that plants would need to colonise bare concrete, with no previous life existing. On could envisage that seeds of some pioneer plants could germinate within cracks forming in the concrete. Some wild animals might take shelter in the degenerating structures, adding nutrients to the ground. Eventually, the walls of the structures would be mostly collapsed, and a layer of soil would cover most of the structure.  

Gravitational force i believe

What orders do you have in your chart