Whats the difference between disjoint and mutually exclusive?

The depth of a lake at a certain point, wich is a function of the distance of that point from shore, is 30 feet.

Determine the relationship of ab and cd given the following points

Elena and her husband marc both drive to work. elena's car has a current mileage (total distance driven) of 15,000 and she drives 23,000 miles more each year. marc's car has a current mileage of 46,000 and he drives 9,000 miles more each year. will the mileages for the two cars ever be equal? explain.