Acarnot engine operates between temperatures of 600 and 321 k. to improve the efficiency of the engine, it is decided either to raise the temperature of the hot reservoir by 41 k or to lower the temperature of the cold reservoir by 41 k. which change gives the greatest improvement

uranium fissions/breaks up giving out energy and neutrons

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.