Answer:
-0.125x + 12.5
Step-by-step explanation:
Answer:
14.99 hours
Step-by-step explanation:
The formula for half-life is given as,
R/R' = 2ᵃ/ᵇ...................... Equation 1
Where R= Original mass of sodium-24, R' = mass of Sodium-24 after disintegration, a = Total time taken for sodium-24 to disintegrate, b = half-life of sodiun-24.
Given: R = 1 kg, R' = 0.0156 kg, a = 90 hours
Substitute into equation 1 and solve for b
1/(0.0156) = 2⁹⁰/ᵇ
Taking the log of both side
log[1/(0.0156)] = log(2⁹⁰/ᵇ)
log[1/(0.0156)] = 90/b(log2)
90/b = log[1/(0.0156)]/log2
90/b = 6.0023
b = 90/6.0023
b = 14.99 hours
b = 14.99 hours.
Hence the half-life of Sodium-24 is 14.99 hours
The surface area of a shape is the amount of space on the shape
When the dimensions are quadrupled, the new surface area would be 16 times the initial surface area
<h3>How to determine the surface area</h3>
The surface area of a rectangular prism is:

When quadrupled, we have:

Factor out 16

Substitute 

The above means that:
The new surface area would be 16 times the initial surface area
Read more about surface areas at:
brainly.com/question/24571594
Answer: -7/2
Step-by-step explanation:
Answer: The number of cubic yards of concrete that are needed is 720.
Step-by-step explanation: The same formula for this type of shape stays the same: l*w*(h or d).
240 * 4 = 960
960 * 0.75 = 720