The upstream of a river can be determined by

-the direction of the mouths of the v shapes on contour lines
-which way is south from the map's compass
-examining the highest elevation on the map
-the direction of the points of the v shapes on contour lines

The great scientist alfred wegener proposed that continents have moved, while other scientists such as t. c.chamberlin argued against wegener. wegener's ideas eventually won, and are now widely accepted, because: a) wegener's ideas were more beautiful, and so were favored by the intellectual elite. b) wegener's ideas did a better job of predicting the results of new observations and experiments. c) wegener's ideas appealed to dead white european males, whereas chamberlin's didn't. d) wegener's ideas appalled dead white european males, and we all know that in this politically correct era, dead white european males cannot get a fair shake. e) wegener won the nobel prize.