Given longitude and latitude coordinates what is the elevation?
Longitude, latitude & elevation are the three independent variables (each not depending on the other two). Coordinates imply longitude and latitude together, excluding elevation.
"Elevation" has no connection with latitude or longitude.
If you have specific latitude and longitude coordinates, you can look at a map of the world and see where those coordinates point to. My hunch is that it will be a mountain of significant height, and the actual height will be noted in feet or metres on the map.
Latitude and Longitude does not give elevation information.
You need to plot the Lat and Long onto a Topographic Map, then look at the contour lines for Elevation.