[单选题]
The half-life of radioactive iodine-137 is 8.0 days. How many v y2f frya 0.mxrn(n:io8v(9t iodine -veh3 2d kw9gh*j+pc wnuclei are necessary toepj+2cvw 39-k*ghdh w produce an activity of $1.0 \; \mu Ci$?
A. $2.9 \times 10^{9}$
B. $4.6 \times 10^{9}$
C. $3.7 \times 10^{10}$
D. $7.6 \times 10^{12}$
Post time 2024-1-22 01:01:29