Answer: 12 N
Explanation: according to Newton second law of motion,
F - Fr = ma.
Where F = applied force = 43 N, Fr = frictional force =?, m = mass of box = 6kg, a = acceleration = 2m/s²
43 - Fr = 6(2)
43 - Fr = 12
Fr = 43 - 12
Fr = 31 N
If applied force (F) is 43 N and the frictional force (Fr) is 31 N.... The resultant forge is 43 - 31 = 12 N