unix command

[lipune]

Hi friend

will you tell me,QN1-
how to know the maximum size of a file in a file structure by using unix command.suppose in a directory there are 20 files how can i know which file have maximum size.
QN2-suppose in a file 100 lines are there i want to print only one line suppose say 50th line and also i want to see a range of line like 40 to 60 line but without using HEAD and TAIL command.
Thank you.

[jsmith]

1. man ls - there is an option you want