Need with a b and c do work for me

Cassie is traveling 675 miles today to visit her brother and his family. so far, she has stopped for gas three times. at the first stop, she put in 7.1 gallons of gas and paid $23.79. at her second stop, she put in 5.8 gallons of gas and paid $19.08. and, at the third stop, 6.6 gallons and paid $20.39. at which stop did casey pay the most for gas?

Solve each quadratic equation by factoring and using the zero product property. x^2 + 18x = 9x

If sr is 4.5cm and tr is 3cm, what is the measure in degrees of angle s? a. 56.3 b. 33.7 c. 41.8 d. 48.2