A 00050 G Sample of Boron Contains ____ B Atoms $\times$

A 0.0050 g sample of boron contains ____ B atoms.

A) 4.6 $\times$ 10^-4
B) 7.7 $\times$ 10^-28
C) 2.8 $\times$ 10²⁰
D) 3.1 $\times$ 10²¹
E) 3.3 $\times$ 10²²