Which statement is true? select one: a. hydroelectric power, a nonrenewable resource, is generated from moving water. b. oil, a nonrenewable resource, is processed to make jet fuel. c. propane, a renewable resource, is used in some heating systems. d. the energy from the sun, a nonrenewable resource, can be converted to electricity in solar cells.

The number to the right of an element's symbol (ex. c-12) identifies the of an isotope.

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.

An object displaces 652 ml of water. the volume of the object is: 0.652 cm³ 6.52 cm³ 65.2 cm³ 652 cm³