=+9.42 The authors of the paper “Short-Term Health and Economic Benefits of Smoking Cessation: Low Birth Weight” (Pediatrics [1999]: 1312–1320) investigated the medical cost associated with babies born to mothers who smoke. The paper included estimates of mean medical cost for low-birth-weight babies for different ethnic groups.

For a sample of 654 Hispanic low-birth-weight babies, the mean medical cost was $55,007 and the standard error

(s/ ) was $3011. For a sample of 13 Native American l bi th i ht b bi th an and standard error were ely. Explain why the two

of individuals to walk in a g ( y Walk Straight?” American Journal of Physical Anthropology [1992]: 19–27) reported the following data on cadence (strides per second) for a sample of n 5 20 randomly selected healthy men:

0.95 0.85 0.92 0.95 0.93 0.86 1.00 0.92 0.85 0.81 0.78 0.93 0.93 1.05 0.93 1.06 1.06 0.96 0.81 0.96 Construct and interpret a 99% confidence interval for the population mean cadence.