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QUESTION 27 In order to choose questions for a final version of a test, the examiners created a graph with difficulty on one axis and discriminability on the other. The examiners should use the questions that O a. fall below the .50 point on the discriminability axis. O b. fall above the .50 point on discriminability and difficulty. O c. fall between .30 and .70 on difficulty and above .30 on discriminability. O d. all above the .50-point on the discriminability axis. QUESTION 28 Why should tests include items from a variety of difficulty levels? a. Good tests encourage students to do their best and a range of difficulty helps less confident students. O b. Students are less likely to guess when there is a wide range of item difficulty. O c. Good tests discriminate at a variety of difficulty levels. O d. Students like to have some easy items because they are more likely to respond correctly by chance