(7th-grade math: word problems: algebra) The price to mail a letter at the post office is $0.55 for the first ounce and $0.32 for each additional ounce. Barbara paid $2.47 to mail her letter. How much did the letter weigh?

For how answer my question this will be the last question can you answer in math subject

Which of the following tables represents exponential functions?

You just purchased two coins at a price of $670 each. because one of the coins is more collectible, you believe that its value will increase at a rate of 7.1 percent per year, while you believe the second coin will only increase at 6.5 percent per year. if you are correct, how much more will the first coin be worth in 15 years?