Ab ? bc and ad ? cd what additional information would make it immediately possible to prove that triangles axb and cxb are congruent using the hl theorem? bx and dx are congruent. ax and cx are congruent. ac and bd are perpendicular. bd bisects angle abc what additional information would make it immediately possible to prove that triangles axd and cxd are congruent using the sss congruence theorem? bx and dx are congruent. ax and cx are congruent. ac and bd are perpendicular. bd bisects angle adc

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.