How would you find the mass of a textbook using height and pressure?

I have a problem with this, the statement is as follows:

Show your calculations for determining the average mass of a textbook using the height of the plunger and the average pressure of a textbook.How would you find the mass of a textbook using height and pressure?
For such a problem,volume is necessarily required.

Thereafter apply the formula:

Pressure=Height x Density x (acc. due to gravity)

Get the value for density and then use formula Density=Mass x VolumeHow would you find the mass of a textbook using height and pressure?
Easy. Imagine you have no money to buy a scale, but you own a bathroom plunger and a low pressure gage.



Just find a piece of PVC pipe in which the plunger fits perfectly..., sort of like a bicycle pump. Set the book on a tray fasten to the plunger handle, and measure the air pressure created in the cylinder by the weight of the book (in psi = pounds per square inch, or a fraction thereof). Then multiply that reading with the square inch area of the plunger head. Using the "height" of the plunger on a scale, without a pressure gage, would require calibration of the plunger handle using the pressuge gage and different size books of known weight, or just standard scale calibration weights.