A passenger of mass 60 kg is brought to rest from 12 m/s in a collision. A safety device increases the stopping time from 0.060 s to 0.24 s. By how much does the magnitude of the mean resultant force on the passenger decrease?
3000 N3000\ \mathrm{N}3000 N
12000 N12000\ \mathrm{N}12000 N
9000 N9000\ \mathrm{N}9000 N
15000 N15000\ \mathrm{N}15000 N