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Acell phone company offers two plans to its subscribers. at the time new subscribers sign up, they are asked to provide some demographic information. the mean yearly income for a sample of 40 subscribers to plan a is $45,000 with a standard deviation of $9,200. for a sample of 25 subscribers to plan b, the mean income is $64,300 with a standard deviation of $7,100. at the 0.025 significance level, is it reasonable to conclude the mean income of those selecting plan b is larger? assume unequal population standard deviations. hint: for the calculations, assume the plan a as the first sample. what is the decision rule? (negative amount should be indicated by a minus sign. round your answer to 3 decimal places.) compute the value of the test statistic. (negative amount should be indicated by a minus sign. round your answer to 2 decimal places.) what is your decision regarding h0 ? reject h0 fail to reject h0 compute the p-value. less than 0.01 between 0.01 and 0.025 between 0.025 and 0.05 between 0.05 and 0.10 greater than 0.10

Rena used the steps below to evaluate the expression , when . step 1: substitute into the expression. step 2: simplify the parentheses. step 3: evaluate the power to a power. step 4: use reciprocals and find the value. in which step did rena make the first error?

Given the linear correlation coefficient r and the sample size n, determine the critical values of r and use your finding to state whether or not the given r represents a significant linear correlation. use a significance level of 0.05. r=0.105, n=15 a: critical values: r= +0.514, no significant linear correlations b: critical values: r= +0.514, significant linear correlation c: critical values: r= +0.532, no significant linear correlation d: critical values: r= 0.514, no significant linear correlation will mark brainliest !