Which of these relations is a function?

If the cost to mail a package is an initial $5 and $0.28 for every pound the total cost to mail a package was $11.27, how much did the package weigh?

The figure shows the front side of a metal desk in the shape of a trapezoid. what is the area of this trapezoid? 10 ft²16 ft²32 ft²61 ft²

Find the area of just the wood portion of the frame. this is called a composite figure. you will need to use your values from problem #2need all exepct 4 answerd if you can