Answer:
464 grams.
Step-by-step explanation:
Amount of substance:
The amount of substance after t years is given by an equation in the following format:
In which A(0) is the initial amount and r is the decay rate, as a decimal.
Co-60 has a half life of 5.3 years.
This means that:
We use this to find r. So
![\sqrt[5.3]{(1-r)^{5.3}} = \sqrt[5.3]{0.5}](https://tex.z-dn.net/?f=%5Csqrt%5B5.3%5D%7B%281-r%29%5E%7B5.3%7D%7D%20%3D%20%5Csqrt%5B5.3%5D%7B0.5%7D)
So
If a pellet that has been in storage for 26.5 years contains 14.5g of Co-60, how much of this radioisotope was present when the pellet was put in storage?
We have that 
, and use this to find A(0). So
[tex]A(0) = 464[tex]
464 grams.
Answer:
732.21 m
Step-by-step explanation:
Given the time taken by cadet to cross an obstacle and swing back to where he started = 5.5 seconds
The formula for a complete oscillation(to and fro) period is
<h2>T = 2π * √(L/g)</h2>
where:
<em>T is the period of oscillations</em><em> - time that it takes for the pendulum to complete one full back-and-forth movement.</em>
<em />
<em>L is the length of the pendulum </em>
<em />
<em>g is the acceleration of gravity, which</em><em> is equal to 9.81 m/s^2 </em>
5.5 = 2 π √(L / 9.81)
5.5/2π = √(L / 9.81)
8.64 = √L / 9.81
8.64 ² = L / 9.81
74.64 = L / 9.81
L = 74.64 * 9.81
L = 732.21 m
Answer: Hi!
So if in the box there are 2 balls and she chose one at random, then she had a 0.5 probability of chose each ball, and then she has a 0.5 probability of choosing the ball that is associated to the correct answer, then she has a 0.5 of getting each answer correct.
Now she has 4 questions, then the probability for getting all of them correct is the product of the probabilities for each one; this is:
0.5*0.5*0.5*0.5 = 0.0625
multiplied by 100%, we get a 6.25% of getting the four answers correct using this method.
Answer:
-8 < x, the answer is B
Step-by-step explanation:
Since its starting from -8 and your going to the greater side of the numberline teh variable will be greater than -8, whenever the circle is filled it just means greater than or equal to depending on which side its going. If its filled in, it means that its greater than or equal to or less than or equal to depending on which side its going towards.
Reminder:
<--------------- Negative side/Lower -----------------------> Positive side/Greater
