What are the challenges in completing an engineering drawing assignment?

[huss10]

Homework Statement

i have an engineering drawing and i try to do it but i couldn't understand , can some one help me with this drawing:
http://im29.gulfup.com/2012-04-14/1334417741112.png

Homework Equations

The Attempt at a Solution

 

[pongo38]

What have you got to do with it? Please explain what is causing you difficulty?