A freight train starts out at 0 miles per hour. After 15 miles the
train is traveling 90 miles per hour. What integer represents the
average increase in speed per mile?

7.25

step-by-step explanation:

we know that 7 equals to 7.0. we also know that 1/4=0.25. so we can add the two together and we get 7.25

ca = ec

cpctc makes it so that corresponding parts of the triangle you proved to be equal are equal, the other options aren't part of the part of the triangles you proved to be equal.