I agree; although, I think the reason behind it is because most Russian Classics, specifically Dostoevsky, use these names in nearly every highly-regarded literary work. For example, The Brothers Karamazov, Crime and Punishment... Tolstoy's War and Peace uses the names also.
So I put Ivan Chernof since the last letter is pronounced more like an "f" since it is at the end is devoiced. It accepted it, but said I had a typo. I was just wondering if there was more than one acceptable way to transliterate, and therefore should be accepted, or if "v" is the only officially correct one?
The already obsolete -for English- (except in a few famous people's names here and there) French transliteration is to write "Tchernoff". Quite confusing though. Cf. Davidoff, Rachmaninoff, Tchaikovsky, Tchekhov (where on Earth would that T come from otherwise). It is commonly encountered in French, but fortunately not anywhere as much in English. Stick to the "Chernov" one.
Ты is informal version of singular "you" , while вы is formal singular and both formal and informal plural you. Ты is used for people same age as you, kids, friends, etc. Вы is used for people older than you, strangers... In this particular sentence вы is better choice, because obviously you don't now this person, so using ты would be considered impolite.