A nationwide test taken by high school sophomores and juniors has three sections, each scored on a scale of20

to80

.In a recent year, the nationalmeanscore for the writing section was51.2

,with astandard deviationof10.5

. Based on this information, complete the following statements about thedistributionof the scores on the writing section for the recent year.

(a) According to Chebyshev's theorem, at least?

56%

75%

84%

89%

of the scores lie between 30.2 and 72.2.

(b) According to Chebyshev's theorem, at least?

56%

75%

84%

89%

of the scores lie between 24.95 and 77.45.

(c) Suppose that the distribution isbell-shaped. According to the empirical rule, approximately?

68%

75%

95%

99.7%

of the scores lie between 30.2 and 72.2.

(d) Suppose that the distribution isbell-shaped. According to the empirical rule, approximately 99.7% of the scores lie between

and

.