Geography latitude/ longitude questions

I will be collecting notebooks tomorrow.

1. What would you tell someone who said geography is only the study of land?
2. Buenos Aires, Argentina is located at 34°S and 50°W, which hemispheres is it in?
    Which cities are located at...
3. 28°N 100°W
4. 37°S 150°E
5. 56°N 35°E