<image>For the function y=f(x), the real number x that satisfies f(x)=0 is called the zero of the function y=f(x). The zero of the function y=x+2 is ____. If the functions y=f(x) and y=g(x) are continuous functions defined on R and some function values are given by the following table:

then when x=____, the function f(g(x)) must have a zero in the interval (x,x+1).