This sculpture designed by Mr. Newman’s colleague, Tia, is shaped like a hollow triangular pyramid. All 3 of the lateral faces are congruent and made of glass. How much glass was used to make the sculpture, if each face has a base length of 4 m and a slant height of 6 m?

A triangular pyramid. The triangles have a base of 4 meters and height of 6 meters.

What is the area of each of the lateral faces? m²
What is the total lateral area of the sculpture? m²

Arandom sample of 15 observations is used to estimate the population mean. the sample mean and the standard deviation are calculated as 172 and 63, respectively. assume that the population is normally distributed. a. with 99 confidence, what is the margin of error for the estimation of the population mean? b. construct the 99% confidence interval for the population mean. c. construct the 95% confidence interval for the population mean. d. construct the 83% confidence interval for the population mean. hint: you need to use excel function =t.inv.2t to find the value of t for the interval calculation.