From the information given, there is a 15 kg mass that needs to be accelerated to a velocity of 2.8m/s² We use the formula: F = m × v. Where F = force, m = mass and v = velocity. In our case, m = 15kg and v = 2.8m/s². Therefore: F = m × v. F = 15 × 2.8. F = 42. Therefore the net force needed to accelerate the 15kg mass to 2.8m/s² is 42 kg m/s² (or 42 Newtons)