What is the slope of the line that passes through (3, -7) and (-1, 1)?

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.

How do i do this? i don’t understand

Given the equation f(x)=a(b)x where the initial value is 40 and the growth rate is 20% what is f(4)