EXERCISES XVII. 1. An observation taken in New York (40° 43' N) showed the altitude of the sun to be 52° 25'. Its declination was found (*Discarded, since Z and a must terminate in the same quadrant.) to be 12° 15'. What was the local apparent time of the observation if it was taken in the morning? 3. Find the altitude and the azimuth of the sun at 3 latitude 47° 38′ N, its declination being 7° 18'. 5. The declination of a star is -26° 19', its altitude is 31°5', and its azimuth is S 18° 9' W. Find the latitude of the observer. 7. Find the local apparent time of sunset in Chicago (41° 50' N) on a day when the declination of the sun is -7° 30'. SUGGESTION. At sunset the altitude of the sun is 0°. NOTE. In practice a correction must be made in problems. of this type for the refraction of the rays of the sun by the atmosphere of the earth. Another correction must be made for the angular radius of the sun. 9. On the longest day of the year the declination of the sun is 23° 27'. Find the length of the longest day in latitude (a) 25°, (1) 45°, (c) 65°. ANSWERS: Exercises XVII. 1. 10:08 a.m. 3. 34° 30', S 58° 20' W. 9. (a) 13h 33m; (b) 15h 26m; (c) 21h 8m. 5. 30° 13' N. 5. 30° 13' N. 7. 5:33 p.m.