the first part of the problem asks them to calculate the work done on the gas when the gas goes from the initial state to the final state shown. here is part of their dialogue: nora: the gas is compressed because the volume decreases. that means that there is work done on the gas, and the work is positive. bob: ok. that's right because we're using the first law with q w. we need to use that area thing to find the work. nora: yeah. we want the area under the line between the dots. bob: that line shows the process, right? nora: yup, that's the one. so the area is one-half times base times height. it's the area of that triangle. bob: but you have to add the area of that skinny rectangle below it, don't you? nora: i don't think so. that bottom dot for the final state tells you where the bottom of the area is. bob: why don't we ever agree? tell you what. we'll each try our own way and let webassign tell us who's right. nora: hmmm... i hope i get the big, green check mark!