Conveyor Belt Project Using MS Project

I have been working on this for a few weeks but I can’t seem to figure out the last four parts of this project.

I need help with parts 3, 4, 5, and 6. Parts 1 and 2 have already been completed.  I have attached a word document containing parts 1 and 2 as a reference, followed by the word document containing the instructions for parts 3, 4, 5, and 6. The MS Project file containing the work I have done so far on the Gantt chart and network diagram is also attached.

If you are willing to help me with this project please attach a new MS Project file for each part. Parts 3 and 4 can be combined into one MS Project file, but part 5 and part 6 should each be on a separate file.