Question 649Navigation General

The correct answer is C) 4°03'W. The question provides the variation was 3°45'W in 1988, and the annual change is increasing 6'. To calculate the variation in 1991, we need to add the annual change for the 3 years from 1988 to 1991. 3 years x 6' per year = 18' increase. Adding the 18' increase to the 1988 variation of 3°45'W gives us a 1991 variation of 4°03'W, which matches answer choice C. The other answer choices are incorrect because they do not properly account for the 3-year increase in variation.