Emissions of sulfur dioxide by industry set off chemical changes in the atmosphere that result in "acid rain." The acidity of liquids is measured by pH on a scale of 0 to 14. Distilled water has pH 7.0, and lower pH values indicate acidity. Normal rain is somewhat acidic, so acid rain is sometimes defined as rainfall with a pH below5.0.

A sample of 105 rainwater specimens had mean pH 5.43; standard deviation 0.54; and fivenumber summary 4.33, 5.05, 5.44, 5.79,6.81.

If the distribution is really (5.43,0.54),N(5.43,0.54), what proportion of observations would be less than5.05?

Give your answer rounded to four decimalplaces.

proportion:

If the distribution is really (5.43,0.54)N(5.43,0.54), what proportion of observations would be less than5.79?

Give your answer rounded to four decimalplaces.

proportion:

Do these proportions suggest that the distribution is close to Normal?Why?

A) Yes, because the quartiles are very close to the quartiles of the Normaldistribution.

B) No, because the Normal distribution has a lower first quartile and a lower thirdquartile.

C) These proportions do not provide information aboutNormality.

D) No, because the Normal distribution has a higher third quartile and a higher firstquartile