A propane tank is in the shape generated by revolving the region enclosed by the right half of the graph of

Question

(4*x^2)+(64*y^2)=144 and the y-axis
about the y-axis. If x and y are measured in meters find the depth of the propane in the tank when it is filled to one-quarter of the tank's volume. (Round to 3 decimal places).

HINT: You will need to use a Graphing Calculator, Online Graphing Calculator, or Computer Algebra System to solve an equation towards the end of your solution to this problem.