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Determine the number of classes in the frequency table below. Class Frequency 27-28 29-30 31-32 33-34 35-36 7 2 6 4 1 0000 NO? [001 Identify the type of sampling used. The names of 30 employees are written on 30 cards. The cards are placed in a bag, and three names are picked from the bag. What sampling technique was used? 0 A. systematic O B. simple random 0 C. stratied O D. convenience O E. cluster A drug company wanted to test a new depression medication. The researchers found 400 adults aged 25-35 and randomly assigned them to two groups. The rst group received the new drug, while the second received a placebo. After one month of treatment, the percentage of each group whose depression symptoms decreased was recorded and compared. What is the response variable in this experiment? the 400 adults aged 25-35 the one month treatment time the type of drug (medication or placebo) 0000 the percentage who had decreased depression symptoms