lab11

http://s9726324.blogspot.com/2011/03/hw3.html?showComment=1300101278766#c7356134473969173275

http://ss9626260.blogspot.com/2011/03/homework-3.html?showComment=1300101394188#c7501351375136559366

http://s9826145.blogspot.com/2011/03/homework-3.html?showComment=1300101438181#c6446806719362304361

http://s9626247.blogspot.com/2011/03/homework-3.html?showComment=1300101602441#c415627987713648908

http://s9726335.blogspot.com/2011/03/homework3.html?showComment=1300101698807#c7825792630624951443