I believe that through deductive reasoning angle O is 64 degrees. The reason is it's bigger than angle R so that rules out 32 and 16 degrees, but it's not obtuse, so that rules out 128 degrees, thereby leaving you with 64. Hope this helps :)
The Range is the difference between the lowest and highest values. Example: In {4, 6, 9, 3, 7} the lowest value is 3, and the highest is 9. So the range is 9 − 3 = 6. It is that simple!