I need some help with some geometry homework

The random variable x is the number of occurrences of an event over an interval of ten minutes. it can be assumed that the probability of an occurrence is the same in any two-time periods of an equal length. it is known that the mean number of occurrences in ten minutes is 5.3. the appropriate probability distribution for the random variable

Ijust need to see how to do this. so you don’t have to answer all of them just a step by step explanation of one.

What are linear equations? could'ya explain too me, ? ! and how do you see what graph is a proportional relationship?