Use autocad to find a complicated angle between two concrete slabs

I am building a small concrete building. The building is rectangular. There are concrete roof panels that angle in on 4 different angles towards the inside of the building. I need to find out what the angle is between the panels. I do not believe it is 45 degrees because each panel angles in at a different degree of slope: South tilts in 18 degrees, North 15 degrees, West 16 degrees and East 24 degrees (these are approximate angles - true angles are to be taken from the autocad drawings. I am hoping you are able to take a section through the building as indicated and a second section through a lower portion of the roof assembly to determine if the angle changes or remains constant. The roof panels are 4" thick (101mm) . The support walls are 5" thick. In plan view the dimension will obviously be wider as we are looking directly down - I need this plan view dimension as well. I only need confirmation of the angles between the roof panels: 1. Between North and West (angle from outside face of panel to joint face between the two panels) 2. Between West and South (angle from outside face of panel to joint face between the two panels) 3. Between South and East (angle from outside face of panel to joint face between the two panels) 4. Between East and North (angle from outside face of panel to joint face between the two panels) I also need a plan view drawing of these four corners in both Autocad and a pdf copy. the pdf copy should show the dimensions, angles and mitres. NOTE: it is possible that the roof panels show a thickness of more than 4". This is the only copy of this Autocad file that I currently have. I have access to Autocad but do not work in it so I am unable to determine if this is the case. The angles will not change because the outside of the building has not changed. Please base your work on these drawings - but indicate if the panels are not shown at 4" thick. The walls are 5" thick. You final drawings will be sent to our engineer for confirmation. This project is intended to have an additional professional (you) check the angles.