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A researcher used his 1 point computer to select a sample of n=100 from a population of 800. Simple Random Sampling O Systematic Random Sampling O Stratified Random Sampling O Cluster Sampling Food delivery riders of Metro 1 point Manila are divided into four groups according to gender and whether they ride a motorcycle or bicycle on their routes. Then 10 are selected from each group and interviewed to determine whether they have been a victim of fake booking in the previous year. Simple Random Sampling O Systematic Random Sampling ! O Stratified Random Sampling