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jenyasd209 [6]
3 years ago
9

An astronaut is working on a satellite 200 miles above the ground. What is the measure of BD⌢, the portion of Earth that the ast

ronaut can see? Round your answer to the nearest tenth. (Earth's radius is approximately 4000 miles.)
Mathematics
1 answer:
natulia [17]3 years ago
6 0

Answer:

420 miles.

Step-by-step explanation:

You would have to be infinitely far away from a sphere in order to see exactly 50% of its surface all at the same moment. Using simple geometry, you can prove that an observer that is a distance d away from the surface of a sphere with radius R can only see a percent area A of the sphere's surface as given by the equation:

A = 50%/(1+R/d)

Where A is the area seen,

R is the earth's radius 4000 miles

And D is the distance above the earth 200 miles

50% = 0.5 in fraction

Substituting values we have

A = 0.5(1 + 4000/200)

A = 0.5(1 + 20) = 0.5 x 21

A = 10.5%

10.5% of 4000 miles = 420 miles.

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Answer:

Step 1 of 4

Point estimate for the population mean of the paired differences = -8.2

Step 2 of 4

Sample standard deviation of the paired differences = 16.116244

Step 3 of 4

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Step 4 of 4

90% Confidence interval = (-17.5, 1.1)

Step-by-step explanation:

The ratings from last year and this year are given in table as

Rating (last year) | x1 | 87 67 68 75 59 60 50 41 75 72

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Step 1 of 4

Mean = (Σx)/N = (-82/10) = -8.2 to 1 d.p.

Step 2 of 4

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Step 3 of 4

Confidence Interval for the population mean is basically an interval of range of values where the true population mean can be found with a certain level of confidence.

Mathematically,

Confidence Interval = (Sample mean) ± (Margin of error)

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It is given mathematically as,

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Critical value will be obtained using the t-distribution. This is because there is no information provided for the population standard deviation.

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Degree of freedom = df = n - 1 = 10 - 1 = 9.

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= (100% - 90%)/2 = 5% = 0.05

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Step 4 of 4

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