Methane is a combustible gas. How does the number of atoms present before a chemical reaction compare to the number of atoms after the reaction is complete?

Acar drives toward the right over the top of a hill, as shown below. which arrow represents the centripetal acceleration? w x y z

This chart shows characteristics of three different types of waves. which statement is best supported by the information in the chart? wave x and wave y are mechanical waves, and wave z is an electromagnetic wave. wave x and wave y are electromagnetic waves, and wave z is a mechanical wave. wave x and wave z are electromagnetic waves, and wave y is a mechanical wave. wave x and wave z are mechanical waves, and wave y is an electromagnetic wave.

You can melt ice by applying pressure because the solid/liquid line has a slope.