Check Columns puzzles

Method explanation: To use the Check Columns method, choose a column, then select a missing number from that column. Then, check the column to see if there is only one possible location for the missing number. If there is only one cell that has that number as a a candidate, the cell is filled in with the missing number.


New Puzzle:
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Using the Check Columns method, which number goes in cell G2?

Example: