#### Answer

a. numerical
b. algebraic
c. algebraic

#### Work Step by Step

A numerical expression is one that includes numbers and operations (such as +, -, $\times$, and $\div$), but NO variables. An algebraic equation is one that includes one or more variables. Keeping this in mind, we can identify (b.) and (c.) as algebraic expressions because there are variables used and (a.) as a numerical expression because there is no variable present.