Answer:
See below
Explanation:
<u>Check One-Sample T-Interval Conditions</u>
Random Sample? √
Sample Size ≥30? √
Independent? √
Population Standard Deviation Unknown? √
<u>One-Sample T-Interval Information</u>
- Formula -->

- Sample Mean -->

- Critical Value -->
(given
degrees of freedom at a 95% confidence level) - Sample Size -->

- Sample Standard Deviation -->

<u>Problem 1</u>
The critical t-value, as mentioned previously, would be
, making the 95% confidence interval equal to 
This interval suggests that we are 95% confident that the true mean levels of lead in soil are between 381.5819 and 398.9181 parts per million (ppm), which satisfies the EPA's regulated maximum of 400 ppm.
As much as the human and physical capital in economy increases, there is a decrease in the marginal gain in economic growth that will diminish.
<u>Explanation:</u>
Low-income countries might have an advantage achieving greater worker productivity and economic growth in the future as their economic growth is faster than the high - income countries.
As much as the human and physical capital in economy increases, there is a decrease in the marginal gain in economic growth that will diminish. And this is called, the laws of diminishing returns.
Secondly, low - income countries find it easier in developing technologies than the high - income technologies especially countries like India and China.
High - income countries put effort in inventing new technologies, whereas low - income countries just improve and improvise their technology.
The claim being made in in the above passage is that " It makes financial sense to stop using the penny." (Option B)
<h3>
What textual evidence backs up the above claim?</h3>
The textual evidence that supports the above claim is "Not only does it make financial sense to take the penny out of circulation, but it also makes environmental sense." [Para. 2]
Textual evidence is evidence related to a text which supports claims made in such a text.
Learn more about claims at:
brainly.com/question/2748145
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