3b i don't get i know the answer is x=-2 and y=-3 i just can't get it

The ratio pv to nrt is plotted against pressure for ch4 at 0°c and 200°c. why does the curve for 0°c drop below the horizontal line for an ideal gas whereas the curve for 200°c does not?

Given the following sampling distribution of one mean with a sample size 49, from a normally distributed population,find the population standard deviation, o.79828588912497

Which is the graph of f(x) = (4)x? image for option 1 image for option 2 image for option 3 image for option 4