Noyes needs to earn a C in his Physics class His current test scores are 66, 65, 81, and 71. His final exam is worth 3 test scores. In order to earn a C Noyes's average must lie between 70 and 79 inclusive. What range of scores can Noyes receive on the final exam to earn a C in the course?
sfinal exam scores
(Type an integer or a simplified fraction)

Malia is observing the velocity of a cyclist at different times. after two hours, the velocity of the cyclist is 15 km/h. after five hours, the velocity of the cyclist is 12 km/h. part a: write an equation in two variables in the standard form that can be used to describe the velocity of the cyclist at different times. show your work and define the variables used. (5 points) part b: how can you graph the equations obtained in part a for the first 12 hours? (5 points) if you can try and make this as little confusing as you can

The fence around a quadrilateral-shaped pasture is 3a^2+15a+9 long. three sides of the fence have the following lengths: 5a, 10a-2, a^2-7. what is the length of the fourth side of the fence?

The anwser cause i do not understand just plez