If the car still produces 8500N, but now it accelerates at only 4 m/s2 what is the MASS of the car?

You can do that yourself, but there's a example question below. And, if for example, I just answer your question and you don't even try to answer. it dosent matter.

Explanation:Force=Mass x Acceleration  -or-  F=ma

where F is the force, m is the mass, and a is the acceleration. The units are Newtons (N) for force, kilograms (kg) for mass, and meters per second squared (m/s2) for acceleration. The other forms of the equation can be used to solve for mass or acceleration.

m=F/a and a=F/m Example:

Engineers at the Johnson Space Center must determine the net force needed for a rocket to achieve an acceleration of 70 m/s2. If the mass of the rocket is 45,000 kg, how much net force must the rocket develop?

Using Newton's second law, F=ma

F=(45,000 kg)(70 m/s2) = 3,150,000 kg m/s2 F=3,150,000 N Note that the units kg m/s2 and newtons are equivalent; that is, 1 kg m/s2

it is the most commonly accepted one