My welding school starts us out on 1/8inch plate 1/16 open root (push and pull) then moves us onto 3/32 gap

I asked my welding instructor the same thing and he said pretty much the same thing. The only difference between 7018 and 11018 is carbon content. As we know, when you go up in carbon content you worry about cracking. A way to prevent this is post heat and preheat.

Shouldn't the ER70s-6 (a really common type of mig wire) be able to cut through that mill scale?

I'm in college studying welding about to graduate. I was wondering about the actual verbal interview part. What should I wear, what sort of interview questions should I be expecting sort of thing.