Answer:
data given
half life of Ra is 1590 years
time for decay is 2000 years
initial amount 300mg
Required final amount
Explanation:
from
nt/no=(1/2)^(t/t1/2)
where
nt is final amount
no is initial amount
t is time for decay
t1/2 is half life
now,
nt/300=(1/2)^(2000/1590)
nt/300=(1/2)^1.26
nt/300=0.42
nt= 0.42×300
nt=126mg
: .it will remain 126gm