A star is estimated to have a mass of 4 x 10³⁶ kg. Assuming it to be a sphere with an average radius of 7.2 x 10⁵ km km, calculate the average density of the star in units of grams per cubic centimeter. Density = g/cm³

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.