[单选题]
How long would it take 2o q5ce jo4f/0ssm,s6e, em wzhmi9*nmg*i la2 w(6+mvp;p ld$4.0 \times 10^{20} \; atoms$ to decay to $1.0 \times 10^{19} \; atoms$ if their half-life was 14.7 years?
A. $29.4 \; years$
B. $58.8 \; years$
C. $78.2 \; years$
D. $147 \; years$
Post time 2024-1-22 01:01:29