If someone with HIV is diagnosed with one of these opportunistic infections (even if the CD4 count is above 200), he or she is said to have AIDS. AIDS usually takes time to develop from the time a person acquires HIV--usually between 2 to 10 years or more.
It has been thought that the wheel was invented in 8000 B.C but the oldest discovered wheel dates back to 3500 B.c. It was discovered in Mesopotamia (nowadays in Iraq). Below are the timelines of wheels and its usage in different era.
The oldest known wheel used for transportation was found by archaeologists in Mesopotamia. It is believed to date back to 3,500 B.C. However, wheels had been in use for hundreds of years before that to make pottery, as it is believed that potters' wheels existed since the Neolithic Era.