Help very urgent, . . .

What are the domain and range of f(x)=[1/5]x

Use set buikder notation to represent the following set: {, -2, -1, 0}

The chs baseball team was on the field and the batter popped the ball up. the equation b(t)=80t-16•16+3.5 represents the height of the ball above the ground in feet as a function of time in seconds. how long will the catcher have to get in position to catch the ball before it hits the ground? round to the nearest second