What process causes hurricanes to form over warm, tropical water?
A.
The thermal energy of the water is transferred to the air above it.

B.
The cold air above the water transfers cooling energy to the warm ocean.

C.
The warm water prevents the Sun's rays from reaching the ocean's floor.

D.
The thermal energy in the air is transferred to the warm water below it.

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.