3. The quality control officer at a manufacturing plant needs to determine what percentage of items in a batch are defective. The following are different sampling techniques that could be used by the officer. Classify each as simple random sample, stratified sample, systematic sample, cluster sample, or convenience sample. a. The officer lists all of the batches in a given month on index cards. The number of defective items is counted in selected batches chosen by a colleague from a jar containing the batches for the month. 5. b. The officer takes the first 10 batches and counts the number of defective items