Again use Table 2.2 to select a sample, but this time select only one random number from Table 2.1. Start in the row determined by the index for that random number. Choose the first value from the first column in that row; then skip the next seven columns and select the second value from column 8. Continue skipping seven consecutive values before selecting the next value.

When you come to the end of the row, continue the procedure on the next row. What kind of sampling procedure is this? Can bias be introduced when you sample in this way?