The "k" value should have units and should be negative.
k = -.07 / seconds
Half-Life = ln (.5) / k
Half-Life = ln (.5) / -.07
Half-Life = -.693147 / -.07
Half-Life = 9.9 seconds
(actually, wkpedia says half-life of Krypton 91 is 8.57 seconds)
elapsed time = half-life * log (bgng amt / end amt) / log (2)
elapsed time = 9.9 * log (100 / 10) / 0.30102999566
elapsed time = 9.9 * 1 / 0.30102999566
<span><span>elapsed time = 9.9 * 3.3219280949
</span>
</span><span><span><span>elapsed time = 32.8870881395
</span>
</span>
</span>
<span>elapsed time = 32.89 seconds (rounded)
Source:
http://www.1728.org/halflife.htm
</span>
Answer:
Yes
Step-by-step explanation:
If the longest side squared is equal to the sum of the squares on the other 2 sides then they form a right triangle
longest side = 7.5
7.5² = 56.25
2.1² + 7.2² = 4.41 + 51.84 = 56.25
Thus the 3 values form a right triangle.
Answer:
Radius: 19 yards
Diameter: 38 yards
Circumference: 119. 32
Step-by-step explanation:
Radius
To find the radius you divide the diameter by 2 because, the diameter is a; a straight line passing from side to side through the center of a body or figure, especially a circle or sphere.
So 38 ÷ 2 = 19
So the radius is 19.
_____________________
Circumference
To find the Circumference you need to do 2·π·19
C=2·π
2·π = 6.28
6.28 · 19 = 119. 32
Circumference is 119. 32
Answer:
A. It Increases
Step-by-step explanation:
Given the expression:
1+3f
When f=1, 1+3f=1+3(1)=1+3=4
When f=2, 1+3f=1+3(2)=1+6=7
When f=3, 1+3f=1+3(3)=1+9=10
We can see that the value of the given expression for each successive term increases and in fact form the sequence
4,7,10,...
Therefore, when f increases, 1+3f increases.