here everything with images
 
 
http://img704.imageshack.us/img704/5520/problem1w.png
http://img704.imageshack.us/img704/2116/problem2j.png
 
http://img530.imageshack.us/img530/5445/problem3.png
 
http://img829.imageshack.us/img829/6345/problem4.png
 

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