Answer:
The graph in the question does not represent a linear function because a linear function is always a straight line, and is represented by the following equation:
y = f(x) = a + bx
The function illustrated in the graph looks more like a logarithmic function that is flattening as it progresses.
George W bush signed the Immigration act of 1990 which allowed over 700,000 immigrants to come to the U.S (and because america is awesome)