A study of 29 female Sumatran elephants provided a 95% confidence interval for the mean shoulder height as (197.2, 235.1) cm. Consider a new study to estimate the mean shoulder height of male Sumatran elephants. Assuming the standard deviations of shoulder heights are similar for males and females, how many male elephants should be sampled so that the 95% confidence interval for the mean shoulder height of males will have a margin of error of 10 cm?