Definately a beginner should not bowl if someone is on the approach on the lane next to them.
The anchor bowler
A bowler is not permitted to cross the foul line.
No. The same bowler must continue the bowling.
No it just as your bowler's ID number on it.
Sean rash in the PBA
Yes
about 227 per game
A bowling enthusiast is called a "kegler."
With the advent of better, lighter bowling balls, there isn't a set average. A lot depends on the ability of the bowler and skills of the bowler.
MIB stands for most improved bowler.
If you are a professional bowler, then yes.
Anyone who participates in bowling could in theory call themselves a bowler. However, someone who always leaves 3 pins when they bowl should likely not consider a professional bowling career.