The ages of rocks in an isolated area are known to be approximately normally distributed with a mean of 7 years and a standard deviation of 1.8 years. using the normalcdf function on your graphing calculator, what percent of rocks are between 5.8 and 7.3 years old?
a. 31.4%
b. 37.5%
c. 3.14%
d. 41.3%

If calculating interest by the previous balance method, purchases and payments during the month __ counted in calculation of interest. a. are b. are not c. must be d. are sometimes

In a recent telephone survey, 5,000 randomly selected teenagers were asked to cite their primary social network site. six of 10 teenagers said they use mybook as their primary social network site. a 95% confidence interval to estimate the true proportion of teenagers who use mybook as their primary social network site is found to be (0.2964, 0.9036). which of the following is a correct interpretation of the confidence level? ninety-five percent of all samples of this size would yield a confidence interval of (0.2964, 0.9036). there is a 95% chance that the true proportion of teenagers who use mybook as their primary social network site is in the interval (0.2964, 0.9036). ninety-five percent of the time, the procedure used to generate this interval will capture the true proportion of teenagers who use mybook as their primary social network site. ninety-five percent of all the samples of size 5,000 lie in the confidence interval (0.2964, 0.9036).

Which of the following contradictions best exemplifies why the democratic party struggled during the 1928 presidential election? a. it tried to appeal to religious fundamentalists along with committed secularists. b. it promoted jim crow laws but saw an influx of african american voters to its districts. c. it was forced to publicly endorse prohibition despite the objections of big businesses. d. it relied on the support of both the ku klux klan and roman catholic immigrants.