cheese
It is called a area.
The perimeter
The line connecting the points is called a chord; the part of the perimeter of the circle enclosed is called an arc; the area between an arc and the chord is called a circular segment.
It is called its perimeter.
border
axis of rotation
A line that goes around the outside of something is called a "perimeter." It defines the boundary of a two-dimensional shape, enclosing the area within. In geometry, calculating the perimeter involves adding the lengths of all the sides of a figure. It's commonly used in various contexts, including architecture, land measurement, and design.
The perimeter is the length around the outside of a shape, or the total of all the lengths of its sides. A shape that consists only of a line is simple: it has two sides, both of which are exactly the same length (from one end to the other and back along the other side of the line). Just measure the line, then double it. That is the perimeter.
out line
It is a tangent line
Yes, a single circular line called the Glasgow Subway.
If it is a circular mirror the line would be called a radius. If it is a rectangular or square mirror it would just be called a diagonal or straight line... nothing special