Intro statistics

This is question 12

# 12 is missing this information at the end “width of the interval to be 0.1 or less.  The minimum sample size required is”?  

I need answers to be concise and annotated details should contain every step used to resolve the homework. Just do it as if i was a kid.

Thanks

Part 1

__MACOSX/._Part 1

Part 2

__MACOSX/._Part 2

Part 3

__MACOSX/._Part 3

Part 4

__MACOSX/._Part 4