Astudy of one thousand teens found that the number of hours they spend on social networking sites each week is normally distributed with a mean of 10 hours. the population standard deviation is 2 hours. what is the 95% confidence interval for the mean?
a) 9.88-10
b) 10-10.12
c) 9.88-10.12
d) 9.76-10.24

If x = ∛200, which of the following inequalities is true? * 2 < x < 4 3 < x < 5 6 < x < 6.5 4.5 < x < 5.5 5 < x < 6

The average hourly earnings for a construction worker is projected to be $24.50 in 2012. jason wants to join the construction work force after he graduates in 2012. his friend tells him that average hourly earnings for construction workers will rise by 2% from 2009 to 2012. based on the data below, assuming that the projected hourly earnings are correct, is jason’s friend’s statement accurate? construction industry - average hourly earnings, 2000-2009 a. his friend’s statement is accurate. the average hourly earnings will increase by 2%. b. his friend’s statement is not accurate. the percent increase will be more than 2% c. his friend’s statement is not accurate. the percent increase will be less than 2% d. his friend’s statement is not accurate. the average hourly earnings will decrease

Aremote-controlled boat can travel at 4 feet per second in calm water. the boat traveled 48 feet with the current, and then it traveled 16 feet against the current in the same amount of time. how fast is the current?