Where is the blue dot on the number line? help pls

I’ve been trying all day to figure this puzzle out. i need the work for it aswell. it is a factoring polynomials tarsia. the image is below.

An object is accelerating at a constant rate. its velocity in feet per second as a function of time in seconds can be modeled by the linear function v(t) = 2.5t. what does the dependent variable represent for this function? a) acceleration b) distance c) slope d) velocity

Ratio of circumference to diameter example plz i need to now what it looks like.