Gauge is 20 sts (4 pattern repeats) in 3.5 inches.
5 buttons, 3 with loop buttonholes and 2 as anchors for a back tab.
Each size is a range and if wanting a longer Cardi add more yarn. 3/4 sleeve is one ball more yarn than short sleeve.
Pattern is Eyelet Cable which gives an up and down overall look.
Short Sleeves are longer than short sleeves on a tee.

Intermediate skill level. The count varies on two rows which makes decreases challenging. You might want to mark sides with different colors when doing front decreases.

Amount required for short sleeved Cardi in recommended yarn: 7 balls for 8-10, 8 balls for 12-14, 9 balls for 16-18, 10 balls for 20-22. Love the colors in the recommended yarn.

The pattern is a 3X2 rib pattern and has some stretch to it. 100% Cotton tends to lengthen.