For cumulative frequency you simply add the previous frequencies up to the interval you’re at.
So frequency for <58.5 is
44(0+7+37) since that’s the number of kettles that have a length less than 58.5 cm
Applying the same logic in the next 2 table places,
77 (44+33) kettles have length <63.5
While
80 (77 + 3) kettle have length
<68.5
