A scientific theory is proposed after several valid investigations. This makes scientific theories (2 points)

elaborate descriptions of observations

the most powerful explanation scientists have to offer

unchangeable by other scientists over a period of time

unacceptable to a majority of scientists

falling water hydro = water .. spectcular places these plants are

luster is not a good characteristic to use by itself because luster is the property of minerals that indicates how much the surface of a mineral reflects light. the luster of a mineral is affected by the brilliance of the light used to observe the mineral surface.

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.