Cane toads are large, poisonous frogs native to Central and South America. They were introduced in Australia in 1935 in an attempt to control the beetle population in the sugarcane fields. Since then, their speed has increased significantly. According to recent studies, scientists have determined that they now have longer legs, are more active, and are larger in size than their ancestors in Central and South America. Which statement best explains why the cane toads in Australia move more quickly than their ancestors?

Nebulae are enormous clouds in outer space. they are made mostly of hydrogen gas, helium gas, and dust. some nebulae glow brightly, while others do not. the stars that people see are huge, bright balls of glowing gas. they are made mostly of hydrogen and helium. which statement correctly describes other ways in which nebulae and stars are different? a. stars can form inside a nebula but a nebula can never be produced by any star. b. a star always has a higher density than a nebula. c. stars can never form inside a nebula but a nebula can be produced by any star. d. a nebula always has a higher density than a star.