1. If $f(x) (x \in R)$ is an even function with a period of 2, and when $x \in [0,1]$, $f(x) = x^{1998}$, then the order from smallest to largest of $f\left(\frac{98}{19}\right), f\left(\frac{101}{17}\right), f\left(\frac{104}{15}\right)$ is