According to a national survey, middle school students read on average 45 minutes per day. The principal of Guilford Middle School is worried that its students read less, and has asked you to investigate. You collect a sample of 50 students and find an average reading time of 39 minutes and a standard deviation of 24 minutes. Using a significance level of o = 1%, what do you conclude? O You do not reject the null hypothesis because the test statistic is greater than the critical value. O You reject the null hypothesis because the test statistic is less than the critical value. O You reject the null hypothesis because the test statistic is greater than the critical value. O You do not reject the null hypothesis because the test statistic is less than the critical value.Suppose you want to test whether consumption and income are linearly related using the estimates from your regression model. The standard error of the slope is [3.143. Set ct = [1.01. What is your conclusion? {3 Reject the null hypothesis because -2.53>-4.D32. {j Reject the null hypothesis because 4.22 >4.D32. {j Fail to reject the null hypothesis because 5.?>3.?D?. {j Reject the null hypothesis because 4.22>3.?D?. Which of the following is not a measure of dispersion? O Mode O Range O Variance O Standard deviationColgate claims that 90% of dentists recommend Colgate toothpaste. Suppose you randomly choose 10 dentists and ask whether they recommend Colgate toothpaste. What is the probability that exactly 7 dentists in your sample recommend Colgate toothpaste? O 0.000 O 0.057 O 0.194 O 0.700