In a poll of 515 human resource professionals, 45.8% said that body piercings and tattoos were big personal grooming red flags.

a. Among the 515 human resource professionals who were surveyed, how many of them said that body piercings and tattoos were big personal grooming red flags?

b. Construct a 99% confidence interval estimate of the proportion of all human resource professionals believing that body piercings and tattoos are big personal grooming red flags.

c. Repeat part (b) using a confidence level of 80%.

d. Compare the confidence intervals from parts (b) and (c) and identify the interval that is wider. Why is it wider?