Answer:
The Ans is this
you are given the all the dimensions of the sheet of metal, with which you can calculate the volume.
2mm=0.2cm
V = 0.2*10*15 = 30cm^3
The definition of density is mass per unit volume. D=m/V
so the density, D= 4g/30cm^3 = 0.133g/cm^3
OR
Density = Area (cubic cm) /Mass (grams)
.2 cm x 10 cm x 15 cm = 30 cm^3 (cubic cm)
30/4 = 15/2
15 cm^3 / 4 grams
