Radium - $226$ Has a Half-Life Of $1600 \text { years }$

Multiple Choice

Radium - $226$ has a half-life of $1600 \text { years }$ ) Suppose we have a $300 \mathrm {~g}$
Sample. How much of the sample remains after $200$ Years?

A) $105.61 \mathrm {~g}$
B) $124.61 \text { g }$
C) $275.1 \mathrm {~g}$
D) $288.1 \mathrm {~g}$
E) $200.1 \mathrm {~g}$