You want to create a spotlight that will shine a bright beam of light with all of the light rays parallel to each other. you have a large concave spherical mirror and a small lightbulb. where should you place the lightbulb?

At the focal point of the mirror.

Explanation:

The light bulb should be placed at the focal point of the concave mirror because when the light rays hit the concave mirror, they will not converge and they will not diverge, the light rays will be reflected in parallel lines.

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.