For older browsers that do not support media queries, Cascading Style Sheets (CSS) provides the keyword to hide style sheets from those browsers.

*write a program that defines symbolic names for several string literals (chars between quotes). * use each symbolic name in a variable definition. * use of symbolic to compose the assembly code instruction set can perform vara = (vara - varb) + (varc - vard); ensure that variable is in unsigned integer data type. * you should also further enhance your symbolic logic block to to perform expression by introducing addition substitution rule. vara = (vara+varb) - (varc+vard).