The following abbreviations have something in common. Can you determine what it is?

1. MA
2. AC

3. OK

4. JD

5. MP

6. PA
7. DC
8. IRA
9. ERA

Answer:

Each abbreviation can stand for at least two different things.

1. MA - Massachusetts and Master of Arts
2. AC - Air conditioning and Alternating current
3. OK - Oklahoma - Okay
4. JD - Juris Doctor - Juvenile delinquent
5. MP - Military Police - Member of Parliament
6. PA - Pennsylvania - Public address
7. DC - District of Columbia - Direct current - Doctor of Chiropractic 
8. IRA - Irish Republican Army - Individual Retirement Account
9. ERA - Earned run average - Equal Rights Amendment