When the brain retains an image of what you were viewing

A refracting telescope uses

A. Mirrors to create the image. B. Only lenses to create the image. C. The name has nothing to do with the information in this chapter.

Massive, more luminous stars have shorter lives than their smaller, dimmer counterparts

Indicate whether the statement is true or false

Based on inventoried matter in the universe, including dark matter known to exist in galaxies and clusters, the actual density of the universe is what fraction of the critical density?

A) 1 percent B) 10 percent C) 26 percent D) 74 percent E) 100 percent

A 1000-kg car and a 2000-kg car are hoisted to the same height. Raising the more massive car requires

A) less work. B) as much work. C) twice as much work. D) four times as much work. E) more than four times as much work.