$\"\"$

There are $\"\"$ nickels in one dollar.

Write an algebraic expression to find the number of nickels in any number of dollars $\"\"$ .

Phrase: $\"\"$ nickels in one dollar.

Variable: Let $\"\"$ represents the number of nickels.

Expressions: $\"\"$ .

Therefore, the algebraic expression is $\"\"$ .

$\"\"$

Find the howmany nickels are in $\"\"$ .

$\"\"$ (Original expression)

$\"\"$ (Substitute $\"\"$ )

$\"\"$ (Simplify)

Therefore, There are $\"\"$ nickels in $\"\"$ .

$\"\"$

a. The algebraic expression is $\"\"$ .

b. There are $\"\"$ nickels in $\"\"$ .