State theobjects i the universe that give out their own light

The roller coaster from problem #1 then tops a second hill at 15.0 m/s, how high is the second hill? 91.5 m 79.2 m 80.0 m 68.5 m

Rank the automobiles based on the magnitude of the force needed to stop them, from largest to smallest.2000 kg car going 5m/s500 kg car going 20 m/s1000 kg car going20m/s500 kg car going10m/s1000 kg car going10/s4000 kg car going 5m/s 0 0 603

What is the major limitation to the light microscope?