The three methods of determining latitudes are:
Celestial navigation - is the use of a celestial body such as the sun, the moon or a star at sight to know your location.
Sextant - is an instrument for navigation the uses two visible objects. The angle between the horizon and a celestial body will determine your location.
Octant - this is also an instrument used for navigation for calculation of angles.
The factor that helped the United States in making the inland transportation and commerce to be possible is in letter C. The intricate river system. I hope you are satisfied with my answer and feel free to ask for more if you have clarifications and questions.
The countries currently on stage 4 of demographic transition model are.. Argentina, Australia, Canada, China, Brazil, Singapore, South Korea, U.S. , and most of Europe.
C. Australia is moving at about ~7 centimeters a year, which is about 67 millimeters.