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On a polar stereographic chart whose grid is parallel with the Greenwich meridian in the direction of the true North pole, the true track of the great circle linking point 62°N 010°E to point 66°N 050°W is 305°. The grid route at the starting point of this great circle is:
  • A
    301°.
  • B
    295°.
  • C
    298°.
  • D
    292°.
Refer to figure.
For this exercises, you can use the following 2 rules:

1) Find convergence. For polar stereographic charts, convergence equals longitude. If in the northern hemisphere, invert direction (East becomes West, and vice versa)

2) Apply the rule. Convergence WEST, True BEST; Convergence EAST, True Least.
Regarding this question:
1) Grid convergence = angle between GN and TN;
on longitude 10ºE => convergence = 10ºW.

2) Convergence is west, therefore true is best:
  • GRID = TRUE - convergence
    GRID = 305º - 10º 
    GRID = 295º

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