The supply curve is a graph that shows quantity supplied at a given price. Quantity is on the x axis and price is on the y axis.
At $8, Maria is willing to supply 35 hours.
at $10, she will supply 40 hours, and at $12 she will only supply 37 hours.
The drop in hours between $10 and $12 makes sense because at $10 working 40 hours she will make $400 dollar. but at $12 she can make more money working fewer hours, and can use her time for other things.
