1- Assume the Earth is approximately a sphere (not an ellipsoid). Also assume

youve repeated Poseidoniuss measurements. What is your estimate of the radius of

the Earths sphere given the following distance/angle pairs. Note that the distances

are given in meters, and angle in degrees, and calculators or spreadsheets may require

you enter angles in radians for trigonometric functions (1 radian = 57.2957795

degrees):

a) angle = 2^o59 31.33325, distance = 332,000 meters

b) angle = 9^o 12 12.77201, distance = 1,020,708 meters

c) angle = 1^o 2 12.15566, distance = 115,200 meters

2- What is a datum transformation? How does it differ from a map projection?

Course code: 225ISM-3 Geographic Information Systems