How do you tell whether the ratios form a proportion

What is the distance between (–2 1/2,-3) and (1, –3)?

An advertising firm has an old computer that can prepare a whole mailing in 6 hours. with the of newer model the job is complete in 2 hours. how long would it take the newer model to do the job alone?

What term best describes a line ans a point that lie in the same plane