Work equals force times distance. When you move an object, you are exerting a force onto it. By exerting a force on the object, you are actually displacing it from its initial position. You cannot apply force to the object without altering its position. Keep in mind that when you exert work, you are exerting energy too. Note that 1 kilojoule = 1000 joules and joules is equal to Newton meter. So,
W = F*d
F = W/d
F = (0.0284 kJ)(1000J/1kJ)(1N-m/1J)/4m
F = 7.1 N