The force a skateboard exerts on you if your mass is 60kg and you push on the skateboard with a force of 60n

the skeletons of most mammals reach a certain size and then stop growing. however, many animals, including some mammals, keep growing throughout their lives. kangaroos, for example, just keep growing and growing until they die. also, the longer an animal lives the greater the chance it might catch some deadly disease.

the right answer is 0.3 meters per second