The expression c=30m + 400, models the total cost (c) to buy a wireless
phone with a data plan for (m) months. Which of the following is not a true statement
about this situation?
1) The phone costs $400.
2) If you spent a total of $1,200, you had the phone for 20 months.
3) If you have the plan for a year, you have paid $760,
4) The data plan costs $30 per month.