Answer: I think it’s A because 8x5=40
Step-by-step explanation:
Answer: 3.712 hours or more
Step-by-step explanation:
Let X be the random variable that denotes the time required to complete a product.
X is normally distributed.

Let x be the times it takes to complete a random unit in order to be in the top 10% (right tail) of the time distribution.
Then, 
![P(z>\dfrac{x-3.2}{\sigma})=0.10\ \ \ [z=\dfrac{x-\mu}{\sigma}]](https://tex.z-dn.net/?f=P%28z%3E%5Cdfrac%7Bx-3.2%7D%7B%5Csigma%7D%29%3D0.10%5C%20%5C%20%5C%20%5Bz%3D%5Cdfrac%7Bx-%5Cmu%7D%7B%5Csigma%7D%5D)
As,
[By z-table]
Then,

So, it will take 3.712 hours or more to complete a random unit in order to be in the top 10% (right tail) of the time distribution.
You need to simplify the improper fraction into a mixed number.
43/4 = 10 3/4 (or 10.75)
You will want to have your answer as a mixed number, but multiplying might be easier if you use the decimal for calculations.
Now you multiply your mixed number or decimal by 3 (3 sections).
10.75 * 3 = 32.25 or 32 1/4
Your answer would be 32 1/4 meters.
Hope this helps :)