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Fill in the blank below. An experiment in which neither the experimental unit nor the researcher in contact with the experimental unit knows which treatment the experimental unit is receiving is called a O randomized block design 0 double-blind experiment 0 matched-pairs design 0 single-blind experiment Identify the type of sampling used. A statistics student is trying to determine the proportion of all people who own cell phones. He interviews everyone in his apartment building to determine who owns a cell phone. What sampling technique was used? 0 A. convenience O B. systematic O c. cluster 0 D. stratied O E. simple random Describe the shape of the distribution. E a O A. The distribution is skewed to the right. 0 B. The distribution is uniform. O c. The distribution is bell shaped. O D. The distribution is skewed to the left