growing up we lived in the country and had to deal with stray or feral cats.
Rule of thumb if the cat will come to you its a stray and make the attempt to take it to the pound if it runs it runs its a feral cat and kill it. Its harsh but is probably sick and will get your healthy animals sick as well.
I passed some one on 270 which was completely clear mind you, they were going maybe 40 with their hazzards on. I was only ableo go 60 due to snow in my wheels causing the car to shake violently if I went any faster.