Environmental engineers, statistics homework help

2. Environmental engineers are using data collected by weather data centers to learn how climate affects the sea ice. Of 502 ice melt ponds studied in a certain region, 100 were classified as having “first-year ice”. The researchers estimated that about 20% of melt ponds in the region have first-year ice. Estimate, with 90% confidence, the percentage of all ice-melt ponds in the region that have first-year ice. Give a practical interpretation of the results.

Construct a 90% confidence interval around the sample proportion of ice melt ponds with first-year ice.

(,)

(Round to four decimal places as needed.)

Interpret the confidence interval practically. Choose the correct answer below.

• Since 20% is in the interval, one can be 90% confident the true proportion of ice melt ponds in the region with first-year ice is 20%.

B. One can be 90% confident the true proportion of ice melt ponds in the region with first-year ice is within the above interval, and there is a 90% chance it is 20%.

C.One can be 90% confident the true proportion of ice melt ponds in the region with first-year ice is within the above interval, though it is probably not 20%.

D.One can be 90% confident the true proportion of ice melt ponds in the region with first-year ice lies at the mean of the above interval, rather than at 20%.

E.Since 20% is not in the interval, one can be 90% confident the true proportion of ice melt ponds in the region with first-year ice is not 20%.