How far from the building should they position their cannon? there are two possibilities (d1

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.

54 degrees incident angle = reflected angle

angle is from normal turned to line of ray