

JIT compiling and byte code morphing and instrumentation. For instance data base persistence is usually done by instrumentation tools, that add instructions to keep track about transactions and modified objects, or new objects that need persisting. And endless more things.
No. The teacher did not have it wrong. Does not mean the student is right … Marty and Luis both had their own pizza. Marty had a big pizza and “only” managed to eat 4/6th of it. Luis had a small pizza, and “only” managed to eat 5/6th of his. If you want to give a nitpicking correct answer: a single pizza does not have (4 + 5)/6th pieces. x/6th implies the pizza(s) were divided into 6 parts … so: it can only be 2 pizzas.