clear 
clc
E1=-0.277;//in V
E2=-0.744;//in V
Ecell_1=(E2-E1);//in V
printf('Ecell_1=%.3f V',Ecell_1)
Ecell_2=(E1-E2);//in V
printf('\nEcell_2=%.3f V',Ecell_2)

//page 539