Volumetric Data and Extraction of predicted graph

Hello All,

I have been working on the experimental data of indentation test of cylindrical specimen of cartilage.

1. If I want to select, higher order polynomial, ogden or other model, it shows that it needs volumetric data. How can I measure volumetric data, if the specimen is cylindrical? 

Also, on the option of D1, D2, D3...... the tick mark is absent.

If I just input the indentation test data and select the option of d1, d2,d3.......... and run the calibration, will the result be correct?

2. How can I extract the raw data of generated predicted graph?

Thanks