A helium balloon occupies a volume of 1.8 L at 5°C.
What volume will it occupy at 85.0°C?

The most efficient way to establish the best possible economizer position is to measure

Identify the electromagnets with poles that are reversed from the electromagnet shown above

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.