### The earth's spherical coordinate system

Consider a rectangular coordinate system with origin at the center of the earth, z-axis through the North Pole, and x-axis through the prime-meridian. Find the rectangular coordinates of Beijing, China (39Ù' 55'N,116Ù' 25'E )degree. A minute is 1/60degree . Assume the earth is a sphere of radius R=6367km. Beijing has coord