Answer:
a. 99.7%
b. 68%
Explanation:
The empirical rule for approximately symmetrical and bell-shaped distributions states that:
68% of the data are among the values (means - sd) and (means + sd)
95% of the data are among the values (means - 2*sd) and (means + 2*sd)
99.7% of the data are among the values (means - 3*sd) and (means + 3*sd). So that,
68% of the data are among the values (180 - 8) = 172 and (180 + 8) = 188
95% of the data are among the values (180 - 16) = 164 and (180 + 16) = 196
99.7% of the data are among the values (180 - 24) = 156 and (180 + 24) = 204