Y-y1=m(x-x1) what does this formula represent ?

How does the brandt line, walt rostow's modernization model, neocolonialism, and walterstein's world systems theory inform and intersect with each other when explaining economic development?

In what way does renewable energy differ form nonrenewable energy?

This is a 2017 topographic map of puerto rico in the united states, and i'm sorry that people there have suffered such a disaster. i want to ask, what do the yellow dots and areas represent on this graph? and the blue area and the little blue circle, and the little blue sign that looks like a signal tower, what do they stand for?