In the hypothesis testing approach of Jerzy Neyman and Egon Pearson, a null hypothesis is contrasted with an alternative hypothesis, and the two hypotheses are distinguished on the basis of data, with certain error rates. Proponents of each approach criticize the other approach.
In geography, relief refers to the highest and lowest elevation points in an area. Mountains and ridges are typically the highest elevation points, while valleys and other low-lying areas are the lowest. Relief is essential to understanding the topography of an area.
folded mountains are like rock layers that are folded like a rug that has been pushed up against a rock. upwarped mountains form when blocks of Earth's crust are pushed up by forces inside Earth. As the rocks erode they form the peaks and ridges.