Both are interlinked....as to make pricing decision you need certain financial knowledge so as to facilitate you in devising a good pricing strategy....this is one example there are so many others..... You can google finance+marketing.....it'll help you..

Weathering is loosing the shape actually it is withering meaning loosing.....erosion normally happens to metals when the excess of oxygen in the air damages the metal....in other words erosion is rusting out of a metal..