360 t½ 180 t½ 90 t½ 45
Hence 3t½=5minutes
t½=5/3 =10minutes.
Alternatively
N=N0(½)T/t½
45=360(½)5/t½
2-3=2-5/t½
-3=-5/t½
t½=-5/-3 =10 minutes
Moraa orina answered the question on April 12, 2018 at 07:28
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