HELP I WILL GIVE BRAINLEST What best replaces the X in the table?

Radioactive Waste

Carbon Dioxide

Sulfur Dioxide

Nitrogen Oxide

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.

Which change to the system wood cause the freely-moving piston to lower?

Describe the forces both attractive and repulsive that occur as two atoms move closer together.