Scientists use the symbol "u" to represent atomic mass unit.
they use the symbol n
symbol
a star
Hans Holbein died in 1543 in London of the Plague.
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 atomic symbol on the Periodic Table of Elements
American Flag
Use the " symbol, eg 4" is 4 inches.
Rectangles