Question 1637Navigation General

The correct answer is D) 35°30'. The zenith distance is the complement of the observed altitude of the sun. The zenith distance is 90° minus the observed altitude. In this case, the observed altitude is 54°30', so the zenith distance is 90° - 54°30' = 35°30'. The other answer choices are incorrect because they do not correctly calculate the zenith distance from the given observed altitude. For example, option A) 14°30' is incorrect because it is not the complement of the observed altitude.