Someone .. you will receive lots of medals in the future because of people looking this question up and giving you medals

matt did an experiment to study the solubility of two substances. he poured 100 ml of water at 20 °c into each of two beakers labeled a and b. he put 50 g of substance a in the beaker labeled a and 50 g of substance b in the beaker labeled b. the solution in both beakers was stirred for 1 minute. the amount of substance left undissolved in the beakers was weighed. the experiment was repeated for different temperatures of water and the observations were recorded as shown.

part 1: which, if any, substance is soluble in water?
part 2: explain how the data you determine solubility for both substances for temperatures 20 °c to 80 °c.