Solving Sudoku puzzles made easy (part 8)

We're doing row nine (the bottom row), missing numbers 2,4,6,9.
Handily, there's only one place the 4 can go so enter that in the middle-bottom box.
We noted earlier on that the very bottom-left cell was either 2,4 or 9. It can't be a 2 because by now there's already a 2 in that bottom-left box. Neither can it be a 4 (there's already a 4 in row nine), so it must be a 9.
So the cell above that, which we had previously marked "2,4,9" (way back in part 1)' must be a 4.

To finish off row nine, we need to put the 2 in the only place it can go and then put the 6 in the bottom-right cell.
Full series here.