Whats the difference between light and value

For the difference command to work, what needs to happen?

In russian churches the number of domes usually matches the number of altars. but this church has only one altar dome, and 21 symbolic ones. what normal construction device does this church lack?

So my science teacher said anything that makes noise can in a way make music, instruments make music, and mayonnaise makes sound. so i have a question, do not report. is mayonnaise a instrument?