1. The problem statement, all variables and given/known data Each of the four wheels of a car pushes on the road with a force of 4.0 x 103 N [down]. The driving force on the car is 8.0 x 103 N [west]. The frictional resistance on the car is 6.0 x 103 N [east]. Calculate the mass of the car. 2. Relevant equations F = ma Fnet = F1 + F2 3. The attempt at a solution Fnet = F1 + F2 Fnet = FA - Ff = 8.0 x 103 - 6.0 x 103= 2000 N [west] Total force of all four wheels: (4.0 x 103 N [down]) x 4 = 16000 N [down] FN = 16000 N[up] But this is only part of the Normal Force, because the rest is coming from the weight of the car. It seems to me that there isn't enough info to find mass?