Whats is this answer to the point p, in scientific notion

1. if events a and b are non-overlapping events, how do you find the probability that one or the other occurs? 2. what does it mean if p(a or b) equals 1?

Twice the sum of a number and 2 is equal to three times the difference of the number and 8. find the number.

What are the domain and range of the function below? a) domain: (-4,0) range: [-2,infinity) b) domain: (-3,0) range: [-2,infinity) c) domain: (-infinity,infinity) range: [-2, infinity) d) domain: [-2,infinity) range: (-infinity,infinity)