EDITED 1/8/16: A contour interval is a the elevation difference between two adjacent contour lines.
Previous person put some ridiculous answer. This one is the correct answer on APEX and does not need improvement.
remote sensing
remote sensing
The term for a geographic locations height above sea level is altitude. In geography this is the vertical distance above sea level. However, it may also be called the elevation because in geography it is defined as a specific point's height on the Earth's surface in relation to sea level.
Remote sensing
energy
less-dense air has a higher temperature
If you were testing how well different dish soaps cleaned the dishes the control group would be dishes washed in plain water.
Meteorologists.
Planar projection
distortion
Wheather
full moon
distortion
Horizon