This question, by asking which graph is decreasing for all values of x, basically asks you to pic the graph that is ALWAYS decreasing. remember that you must read graphs from left to right, the same way you read a book.
the second two graphs you attached can't possibly be your answer. the third graph is constant, until it sharply INCREASES. because the x values start increasing at some point, it's wrong--you only want decreasing x variables. the same thing goes for the fourth graph--it's increasing, then levels out, then continues increasing.
for the first two graphs, follow the shape of the graph from left to right. graph 1 is inclining, going up, INCREASING. graph 2 is falling, and therefore decreasing. graph 2 is the graph that decreases for all values of x.
Decrease of 25% means only 855 people? Okay, so you want to backtrack. If you divide by 25% you’re going to get what it was for a 75% decrease. So divide by .75 instead. 855/.75 = 1140 unemployed residents last month