The half life of radium is 1690 years. if 80 grams are present now, how much will be present in 830 years
1 answer:
Answer:
A(t) = amount remaining in t years
= A0ekt, where A0 is the initial amount and k is a constant to be determined.
Since A(1690) = (1/2)A0 and A0 = 80,
we have 40 = 80e1690k
1/2 = e1690k
ln(1/2) = 1690k
k = -0.0004
So, A(t) = 80e-0.0004t
Therefore, A(430) = 80e-0.0004(430)
= 80e-0.172
≈ 67.4 g
Step-by-step explanation:
You might be interested in
Answer:
5 * 5 * 5 * 5
Step-by-step explanation:
Use the rules of Indices.
5⁶⁻²
= 5⁴
Answer:
mass is less than the red
speed is equal
energy is less than
Step-by-step explanation:
Hope this helps!
-75 times 5 = 30
Add 75 to 30 =105
105 divided by 5= 21
Kakapo should be 21 inches. Hope this helps sorry if wrong!
Answer:
Step-by-step explanation:
39). y = 
x + 3
40). m = 
y - 
= m( x - 
)
(- 7, 5)
( - 12, 4)
m = ( 4 - 5 ) / ( - 12 + 7) = 1/5
y - 5 = (1/5)(x + 7) ⇒ y = 
x + 6.4
Answer:
There are 180 degress in a triangle. so minus the angles given from 180 to find X.
X = 180 - 106 - 30
X = 44 degrees
