A team of eight dogs pulls a sled with waxed wood runners on wet snow (mush!). The dogs have average masses of 20.0 kg, and the loaded sled with its rider has a mass of 225 kg. (a) Calculate the magnitude of the acceleration (in m/s2) starting from rest if each dog exerts an average force of 175 N backward on the snow. m/s2 (b) What is the magnitude of the acceleration (in m/s2) once the sled starts to move? m/s2 (c) For both situations, calculate the magnitude of the force (in N) in the coupling between the dogs and the sled. Fpart (a) N Fpart (b) N