1). At the posted coordinates, look around and you will see a wall mural with a date. Subtract 1569 from the date and that's the number of feet you must walk in a north, northwesterly heading. Stay to the sidewalk (no need to cross the street) and you will be fine.
2). Here you will be at a historic city of Atlanta landmark. There should be an odd-colored lamppost in front of you. Note its color. Also note the two-digit number that distinguishes this landmark from other stations of its kind in the city. Multiply that by 25 and subtract 15. That's the number of feet you need to travel. For the general direction, if the color is A). Black, travel west; B). red, travel east C). blue, travel south; D). green, travel north. Again, stay to the sidewalk and you will be fine.
3). Here on your left you should notice two large rocks buffering a lane of street on either side. In between the rocks is a patch of grass. Add the four numbers from the date on the mural at the start of your walk to get a two-digit number. Add this number to the station number of the odd-colored bench. Double this result and that's the number of feet you will need to travel in a north-northeasterly direction (stick to the grass) to the letterbox, which is at the base of a tree. Please be mindful of muggles and keep the cache covered!
Good luck!
Please make sure to leave the stamp and its stamp pad in the cache for others. They are not meant to be swag items. Thanks!