that gotta be square inch
penny wide=19.05 milimeter
area av serkel=pi*radius*radus=3.14159265* 9.525^2
=285.0229567 square mm
or 2.850229567* 10^-4 square meter
1 square meter=1550.0031 square inch
so 3612 sq inch =2.33031807 sq meter
2.33031807 sq meter / 2.85022967*10^-4=0.817589606*10-4
or 8.17589606e-5