CHEM HELP? Specific heat problems

As soon as look at the parallelogram abcd shown below: the table below shows the steps to prove that if the quadrilateral abcd is a parallelogram, then its opposite sides are congruent: which choice completes the missing information for reason 5 in the chart? (6 points) congruent parallelograms congruent triangles similar angles similar triangles

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?

I’m stuck on this equation, anyone got the answer?