David's new bike can accelerate from rest to 45.0 m/s in just 6.00 s. the combined mass of david and his bike is 225.43 kg. what is the magnitude of the net (unbalanced) force that can cause the acceleration?

It's a snowy day and you're pulling a friend along a level road on a sled. you've both been taking physics, so she asks what you think the coefficient of friction between the sled and the snow is. you've been walking at a steady 1.5m/s, and the rope pulls up on the sled at a 32 ∘ angle. you estimate that the mass of the sled, with your friend on it, is 65 kg and that you're pulling with a force of 80 n .