Show Timer Question Completion Status: QUESTION 1 The stimulant Ritalin has been
ID: 3356201 • Letter: S
Question
Show Timer Question Completion Status: QUESTION 1 The stimulant Ritalin has been shown to increase attention span and improve academic performance in children with ADHD. To demonstrate the effectiveness of the drug, a researcher selects a sample of n 25 children diagnosed with the disorder and measures each child's attention span before and after taking the drug. The data show an average increase of attention span of 6.8 minutes (mean difference) with a standard deviation of s = 5.5. State the alternative hypothesis O Ritalin does not increase attention span in children with ADHD. O Ritalin increases attention span in children with ADHD. QUESTION 2 Calculate the Critical Value using a two-tailed test and alpha .05. O plus or minus 1.711 O plus or minus 2.064 plus or minus 2.060 Click Save and Submit to save and submit. Click Save All Answers to save all msers ave All Answen MacBook ProExplanation / Answer
Answer - 7:
Numeraator degrees of freedom = k - 1 = 3 - 1 = 2
Denominator degrees of freedom = N - k = 12 - 3 = 9
Hence by using F table,
Critical value = 4.26
Option A is correct.