Hi all!!

I have three questions I need answered for my java programming course. I need these answered in writing explaining the reasoning behind the answer. Examples are okay as ling as there is a written out explanation upon each example!

1) "what happens when change data by reference?"

2) "When should you use a StringBuilder instead of a regular string? What are some advantages of using one versus the other?"

3) "Why do you see an odd string of characters like ("@5acf9800") when you print an array with System.out.println()?"

-Thank you in advance!!