You will be using paper aluminum and lead sheet metal as abs

You will be using paper, aluminum, and lead sheet metal as absorbers for the radiation. which material has the greater areal density (that is, mass per unit area g/cm2)) therefore, presenting more matter to the passing radiation

Solution

Radiation

Using paper, aluminium and lead sheet metal

The material that has greatest area density = Lead (density 11.34 g/ml), therefore presenting more matter to the passing radiation.

followed by aluminium (density 2.7 g/ml)

paper is the thinnest of all through which all radiation passes easily.