A Certain Radioactive Sample Contains 2 $\times$ 10³ Nuclides at a Certain Time (T = 0);3

Multiple Choice

A certain radioactive sample contains 2.4 $\times$ 10³ nuclides at a certain time (t = 0) ;3.0 h later the sample contains 6.0 $\times$ 10² nuclides.
-The value of the rate constant for this process is:

A) 2.2 h^-1
B) 4.6 $\times$ 10^-1 h^-1
C) 1.6 h^-1
D) 3.0 h^-1
E) none of these