What are the various uses of radioactivity in healthcare? What are the future trends in healthcare with respect to the use of radioactivity?

Answer 1

X-rays

Answer 2

im almost positive that Kemo-Therapy for cancer treatment uses Radioactivity

Answer 3

It is true that radioactivity is used for the treatment of cancer but that is NOT chemotherapy. Chemotherapy is the use of chemicals to treat diseases (not just cancer). Radioactivity is used for radiodating (the use of carbon, uranium, K-40, etc to determine the age of fossils, the earth, and objects. Also it is used to sterilize foods, etc.
Here are two sites that contain much more information.

http://www.ndt-ed.org/EducationResources/HighSchool/Radiography/usesradioactivity.htm
http://www.chem.duke.edu/~jds/cruise_chem/nuclear/uses.html