Which is a good plan for backing up data?

Sam is a data analyst at an advertising firm. he often uses a spreadsheet that contains media ratings details. he would like to filter the spreadsheet data based on different filter criteria. which operators can he use to specify the combination of filter criteria? sam can use the ( blank ) operators to specify a combination of filter criteria.

When you reach a yield sign, yield to cross traffic and before you enter the intersection. a. flash your headlights b. wait for a signal c. wait five seconds d. wait for a safe gap

Which of these is most responsible for differences between the twentieth century to the twenty-first century?