The radius of a circle is 9 m. Find its area in terms of \piπ.
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Answer:
The expression that represents the number of days until only 10% remains is T((d) 10 %) =100×.
Step-by-step explanation:
The equation for half life is of the form
A = A₀×.........................................................................(1)
Where
A = Final amount
A₀ = Initial amount
t = Time
h = Half life
For the equation T(d) = 100×2⁽⁻²⁾....................................(2)
We have by comparison with the equation for half life
2 ≡ and and the equation (2) can be written as
Percentage remaining after 2 half lives is
×100=100×
However if the half life of Technetium-99m is 6 hours then we have for one day
×100=100×
Therefore an expression that represents the number of days until only 10% remains is
×100=100×
= 10 %
=
= ㏑ = ㏑(
)
= ×㏑
= ㏑(
)
=
= 3.322
Therefore the expression for the number of days 10 % of Technetium-99m will be remaining is
T((d) 10 %) =100×