Find the eccentricity of ellipse $\large\frac{x^2}{64}+\frac{y^2}{100}=1$?

Question

$\begin{array}{1 1}(a)\;\large\frac{3}{4}\\(b)\;\large\frac{3}{5}\\(c)\;\large\frac{3}{8}\\(d)\;\large\frac{5}{3}\end{array}$