% of Se in peroxidase anhydrase enzyme is 0.5% by weight then minimum

% of Se in peroxidase anhydrase enzyme is 0.5% by weight then minimum molecular weight of peroxidase anhydrase enzyme is
a.)1.5 � 10raised to power 3
b.)15.68
c.)2.168 � 10 raised to the power 4
d.)1.568 � 10 raised to power 4

Atomic mass of selenium = 78.4
Minimum molecular mass =(100 x 78.4)/0.5 = 78400/5
= 15680
= 1.568 x 104 .