How do i prepare for the psat? every time i take a practice test, i get stuck on a problem that is within my topic range, but for some reason i cannot understand it. whenever i look at the explanation, i get it, but i cannot do it on my own. any idea how i can efficiently prepare for it?

(05.02) mr. morris is going to save money and replace his sailboat's mainsail himself. he must determine the area of the mainsail in order to buy the correct amount of material. calculate the area of the parallelogram to determine how much material should be purchased. be sure to explain how to decompose this shape into rectangles and triangles. describe their dimensions and show your work.