Changing Column Width
You can change the width of columns by clicking and dragging the side of a column. The editor will lock slightly at halves (50%), thirds (33%, 66%), fourths (25%, 75%), fifths (20%, 40%, 60%, 80%), sixths (16.7%, 83.3%), and tenths (10%, 30%, 70%, 90%).
Widths can be reset and equalized for an entire row by pressing the width equalize button in the row's object control bar: