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Which of the following parameters may be adjusted to influence the efficiency of a GC separation? (note there may be more than one correct response)

What term refers to the ability to distinguish two peaks from one another in a chromatogram?

(03.02 MC) James believes the honor roll students at his school have an unfair advantage in being assigned to the math class they request. He asked 500 students at his school the following questions: “Are you on the honor roll?” and “Did you get the math class you requested?” The results are shown in the table below: Honor roll Not on honor roll Total Received math class requested 315 64 379 Did not get math class requested 41 80 121 Total 356 144 500 Help James determine if all students at his school have an equal opportunity to get the math class they requested. Show your work and explain your process for determining the fairness of the class assignment process. (10 points)

Rank the following ways of optimizing selectivity in GC in the order in which you would use them experimentally – take into account both effectiveness and speed:

Which compound will have the highest Retention (Capacity) Factor (k)?

(01.03 MC) The Kelly school district gives awards to its schools based on overall student attendance. The data for attendance are shown in the table below, where Min represents the fewest days attended and Max represents the most days attended for a single student: School Min Max Range Mean Median IQR σ High School M 128 180 52 141 160 55.5 41.5 High School N 131 180 49 159 154 48.5 36.5 High School P 140 180 40 153 165 32.5 31.5 Part A: If the school district wants to award the school that has the most consistent attendance among its students, which high school should it choose and why? Justify your answer mathematically. (5 points) Part B: If the school district wants to award the school with the highest average attendance, which school should it choose and why? Justify your answer mathematically. (5 points) (10 points)

Which flask shows the correct end point color for a phenolphthalein titration?                     I.                                                 II.                                          III.

Increasing the flow rate from 1 to 3 mL/min. may result in a satisfactory separation in one third of the time?

What is the main reason for changing to an isoelutropic mobile phase composition?

(03.02 MC)  Maryann is testing the effectiveness of a new acne medication. There are 100 people with acne in the study. Fifty-five patients received the acne medication, and 45 other patients did not receive treatment. Thirty of the patients who received the medication reported clearer skin at the end of the study. Twenty-two of the patients who did not receive medication reported clearer skin at the end of the study. What is the probability that a patient chosen at random from this study took the medication, given that they reported clearer skin? (5 points)