A Certain Substance Has a Half-Life Of $5.0$ Hours How Many Nuclei of the Substance Are Required to Many

Multiple Choice

A certain substance has a half-life of $5.0$ hours. How many nuclei of the substance are required to give an initial activity of $6.0 \mu \mathrm { Ci }$ ? $\left( 1 \mathrm { Ci } = 3.7 \times 10 ^ { 10 } \mathrm {~Bq} \right)$

A) $5.8 \times 10 ^ { 9 }$ nuclei
B) $8.5 \times 10 ^ { 8 }$ nuclei
C) $3.2 \times 10 ^ { 9 }$ nuclei
D) $2.4 \times 10 ^ { 9 }$ nuclei
E) $6.3 \times 10 ^ { 8 }$ nuclei