//Example 3.2//
rCu=0.128;//nm //atomic radius copper (From appendix 2)
a=(4/sqrt(2))*rCu
mprintf("a = %f nm",a)
//The density of the unit cells is
a1=4;// atoms
b1=63.55;//gram //atomic mass of copper
c1=0.6023*10^24;//atoms// Avogardo's number
d=10^7;//nm/cm
p=(a1/a^3)*(b1/c1)*d^3
mprintf("\n p = %f g/cm^3",p)