Give the coordinates for the letters B. C and D in Figure What letters are at these coordinates? a. \( 20^{\circ} 10^{\prime} \mathrm{N}, 71^{\circ} 30^{\prime} \mathrm{W} \) b. \( 20^{\circ} 20^{\prime} \mathrm{N}, 72^{\circ} 00^{\prime} \mathrm{W} \) Name the two hemispheres where each of the above

Below is one acceptable solution. (There is more than one correct way to answer this type of problem.) In the diagram that was used in class or in your text a map grid was drawn so that various letters were marked at the intersections of certain lines of latitude and longitude. For example, one common arrangement was as follows:   • Letter B was placed at the intersection of 20°00′ N and 71°30′ W.   • Letter C was placed one “step” north (i.e. 10′ higher in latitude) at 20°10′ N, 71°30′ W.   • Letter D was placed another step north at 20°20′ N, 71°30′ W. Then, if you are asked later to “locate” points given by coordinates you use the same grid. For instance:  a. The point at 20°10′ N, 71°30′ W falls exactly where letter C is placed.  b. The point at 20°20′ N, 72°00′ W is one grid‐step to the west (a full 30′ of longitude westward) from the vertical line through letters B, C, and D. In the diagram from our text this point is marked with the letter A. Finally, note that in each of the coordinate pairs the latitude is given with an “N” (that is, north of the equator) and the longitude with a “W” (that is, west of the Prime Meridian). Therefore both locations are in the Northern Hemisphere and in the Western Hemisphere. To summarize one acceptable answer:  • The coordinates of the letters in the given figure are approximately:   – B: 20°00′ N, 71°30′ W   – C: 20°10′ N, 71°30′ W   – D: 20°20′ N, 71°30′ W  • When locating the points:   – 20°10′ N, 71°30′ W is at letter C.   – 20°20′ N, 72°00′ W is at letter A.  • Both points are in the Northern Hemisphere (because of “N”) and in the Western Hemisphere (because of “W”). Any answer that shows the proper reasoning and gets these relationships correct is acceptable. (Since the actual letter-placement diagram can vary from text to text, what is important is that you correctly read a latitude–longitude grid and note that “N” means north of the equator and “W” means west of the Prime Meridian.)