by how much in mm will a steel rod 20 m expand when heated from 20 c to 45 c if expansivity of steel is 12×10³​

chemical properties of thing

multiply 2kg by latent heat of vap

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.