How many type of expansion physic

If 21.2 kcals of energy is released by this reaction, how many kj does the reaction release? (1 cal 4.184 j)

Explain to someone who knows nothing about fossils the study of invertebrate paleontology and how it scientists understand the history of the earth. be sure your explanation contains a minimum of two complete sentences.

The speed of sound in ice, water, and steam is shown. what best explains the speed of sound in different states of matter? sound travels fastest in ice because energy is easier to transfer when the molecules are close together. sound travels slowest in steam because the sound has to move around the gas molecules that are far apart. sound travels fastest in ice because the temperature of solids is always greater, so the heat transfers the sound energy. sound travels slowest in steam because the pressure is so great the sound cannot travel though the steam particles.