a star
Usually a circle with a star in it. Although on some maps it may be a circle with a dot in it.
Scientists use the symbol "u" to represent atomic mass unit.
The capital sigma symbol (Σ) is typically used to denote summation in mathematics, not to represent a universal set. A universal set is usually denoted by the symbol "U" or sometimes "ξ" (xi) in set theory. Using symbols consistently is important for clarity, so it's best to stick with conventional notation for representing sets.
they use the symbol n
symbol
The Mayans
chemical symbol
If you are talking about math then its usually " x " but if that is already use in the expression and you want to use another symbol to represent a DIFFERENT number then you can use y or a or so on.
The capital sigma. The capital sigma. The capital sigma. The capital sigma.
On most maps and charts, it is a star that is the state capital.
The atomic symbol on the Periodic Table of Elements
American Flag