The data set fosdata :: plastics gives measurements of plastic microfibers found in the snow in the Arctic and Europe.

a) Using the output of t.test(plastics$diameter, mu = 20) (provided below) give the estimate of the mean diameter of the plastic microfibers found in the snow.

b) Give the 95% confidence interval for the population mean diameter of the plastic microfibers found in the snow. Write a sentence that can be used to present the confidence interval.

c) Test the hypotheses H0 : = 20 versus HA : 6= 20. Write a sentence that can be used to present the evidence provided by the hypothesis test.

library (fosdata) t . test (plastics$diameter, 20 # # One Sample t-test # # # data: plasticsSdiameter -2.5771, df -148, p-value - 0.01094 alternative hypothesis: true mean is not equal to 20 95 percent confidence interval : 16 .92207 19. 59357 sample estimates. mean Of 18 .25792