2. Systems of Linear Equations Ann calls her Swedish aunt 12 times a year. Her calls usually last between 20 minutes and 2 hours. Suppose AT&T charges $6.01 for a 7-minute call to Sweden and $6.79 for an 8-minute call to Sweden. Suppose that MCI charges $0.66 a minute plus a $1.99 overseas connection fee. a. Write a function that represents how much AT&T charges. Define your variables. b. Write a function that represents how much MCI charges. Use the same variable definitions as you did in part (a). c. Use an algebraic method (solve the two equations from parts (a) and (b) using substitution) to determine the length of a phone call that results in the same charge for both companies.