Answer:
Catron's error is
"She did not follow order of operations"
Step-by-step explanation:
Catron evaluates the expression (negative 9) (2 and two-fifths)
That expression can be written as below

Catron's error is
"She did not follow order of operations"
The corrected steps are
Step1: Given expression is 
Step2: Convert mixed fraction into improper fraction
Step3: Multiplying the terms

Therefore solution 
Answer:
The answer is A
Step-by-step explanation:
We need to multiply 1876 by 12. 1876 * 12 = 22, 512. That's our answer
The diffusion time of the red blood cell to take oxygen through the membrane is 25uS.
The small capillaries in the lungs are in close contact and it takes a red blood cell 0.5 seconds to squeeze through the capillary.
The diffusion time for the oxygen across the 1 um thick membrane separating the air is given by,
t = x²/2D
Where,
t is the diffusion time,
x is the thickness of the membrane,
D is the diffusion coefficient.
Putting values,
t = (1 x 10⁻⁹)²/2 x 2 x 10⁻¹¹
t = 10⁻⁷/4
t = 25 x 10⁻⁹ seconds.
t = 25 uS.
so, the diffusion time is 25uS.
To know more about Diffusion, visit,
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The number of shelves stephen can make is approximately 27
<h3><u>Solution:</u></h3>
Given that Stephen makes wooden shelves for his room
Stephen wants to make the shelves 3/4 foot long
He starts with a board that is 20 feet long
To find: number of shelves he can make
So the number of shelves stephen can make can make is found out by dividing 20 feet long board by 3/4 foot long


So the number of shelves stephen can make is approximately 27
An expression that represents the perimeter of the rectangle would be:
P = 2(3n+2) + 2(n-1)
Hope this helps!