How to work this out in geometry form?

Plz need answer now will mark which situations represent linear functions? check all that apply. a)the temperature rises and falls over the course of a day. temperature is a function of time. b)a baseball is hit into the outfield. the height of the ball is a function of time. c)a car goes 55 mph on the highway. distance is a function of time. d)a child grew 2 inches this year and 1 inch last year. height is a function of time. e)a movie director makes 2 movies per year. the number of movies is a function of the years.

Having a hard time understanding this question (see attachment).

Which is an x-intercept of the graphed function? (0, 4) (–1, 0) (4, 0) (0, –1)