Answers:
Yes, yes and yes.
Not newly Yahoo, but your ISP and probably every server on the Internet between your PC and Yahoo will enjoy a history of what you own be up to. Its also impossible to erase. It's unlikely that anyone will ever bother following the trail, but if you become a party of interest at some stage in the subsequent 20-30 years for anything rationale you may find that fragments of your chronological energy on the network come rear legs to regular place you.
Check out the intermingle below on how to become anonymous.
they see ur ip number adjectives the time newly incase ur are barred
yes they can do ANYTHING.
I am sure it is. If you dream up logically i.e. how the police take in for questioning the predators and how the stalkers bring back caught. I am sure they enjoy a program to capture same IP numbers.
yes but the computer might own more than 1 user mightnt t?