Determine the interval(s) on which the following function is continuous. Then evaluate the given limit: f(x)=f(x).
a) Continuous on (−[infinity],[infinity]); Limit =f(x)
b) Continuous on [0,[infinity]); Limit =f(x)
c) Continuous on (−1,1); Limit =f(x)
d) Continuous on [1,[infinity]); Limit =f(x)