For blood or urine sample, cocaine is out of your system in about 48hrs, unless they are going to take a hair sample (very unusual). Cannabis (marijuana) however remains detectable for up to 3 months!
THC metabolizes in your blood very quickly and should be out of it within a day. Drug tests that measure your blood only check what is currently in your system.
3months
2 days
Roman Legions
Abraham Lincoln
3 months
Alcohol for a swab test go back
NO... this is not true! The furthest back a drug test can go is about 6 moths if they use a sample of your hair. Urine drug test can only go back as far as a month.
golf origins can be traced back to the 12th century, but it is unclear who really created it.
7 years
10years
20 years ago, and it was created by Joe Lowther.
Not necessarily. You can trace back your family tree with good research. You may be able to go back hundreds of years. It depends on how far you want to be able to go back. DNA may only be of use if you have other people to test. You can't really do that without knowing who to test. That will take some research to find out who might be related to you. So you will need to do your research, with or without DNA.
Your heritage goes all the way back to the very very beginning. However, no one is able to trace their ancestry that far, and few are able to trace back more than a 200 years or so.