Answer
greater than $932^oF$
Work Step by Step
Using $F=\dfrac{9}{5}C+32$ or the Fahrenheit conversion of Celsius, then $500^oC$ is equivalent to
\begin{array}{l}\require{cancel}
F=\dfrac{9}{5}(500)+32
\\\\
F=900+32
\\\\
F=932
.\end{array}
Hence, at $\text{
greater than $932^oF,$
}$ glass is liquid.