What is the relative position, velocity, and acceleration of car B to car A?

[sweet_girl123]

Homework Statement

Car A is traveling east at 20m/s toward the intersection, car B from rest 40 m North of the intersection and moves south steadily gaining speed at 2.0 m/s^2. six second after A crosses the intersection find 1) position of B relative to A 2) the velocity of B relative to A, C) the acceleration of B relative to A...(it should include unit vector i and j)

Homework Equations

none

The Attempt at a Solution

I got the ans for A)
r=(120 m)i + (4.0 m) j
but can't find the rest of it

 

[Ignea_unda]

Homework Statement

Car A is traveling east at 20m/s toward the intersection, car B from rest 40 m North of the intersection and moves south steadily gaining speed at 2.0 m/s^2. six second after A crosses the intersection find 1) position of B relative to A 2) the velocity of B relative to A, C) the acceleration of B relative to A...(it should include unit vector i and j)

Homework Equations

none

The Attempt at a Solution

I got the ans for A)
r=(120 m)i + (4.0 m) j
but can't find the rest of it

Alright, when considering "relative" speed, remember that it means that you are pretending that car A is completely stopped. As such, what do you need to do with its velocity and acceleration?