14. A private school offers 14 courses. The school is divided by age and 20% of the students in each age group is sampled. This type of sampling is called a) simple random sampling b) systematic random sampling c) stratified random sampling d) cluster random sampling 15. A police officer surveys every 10th driverkor random check up at the border. This type of sampling is called a) simple random sampling b) systematic random sampling c) stratified random sampling d) cluster random sampling students are selected to be surveyed. This