Here are the prices of some items and the amount of sales tax charged on each in Nevada. cost of item ($)
sales tax ($)
10
0.46
50
2.30
5
0.23

What is the sales tax rate in Nevada?
Write an expression for the amount of sales tax charged, in dollars, on an item that costs c dollars.

please help me i don't know what to do

Agroup of students want to create a garden. they do not know the exact measurements but they propose using a variable to represent the length and width of the garden. the length of the garden is 10 feet longer than double the width. use a single variable to write algebraic expressions for both the length and width of the garden. write an algebraic expression for the area of the garden. use mathematical terms to describe this expression.