[填空题]
A rational function is defineqmhik7rav u: p -4(i9ud bw-vefk91bmlc4 w,pc. eqn m+ 1y $ f(x)=a+\frac{b}{x-c}$ , for $x \neq c$ , where a, b, c $\in \mathbb{Z}$. The following diagram represents the graph of y=f(x) .
Using the information on the graph,
1. state the value of a and the value of c ; a = c =
2. find the value of b . b =