What causes heat energy when you rub two objects against each other? (2 points) Group of answer choices

The air around the objects

The flow of heat from one object to the other

The friction between the two objects

The pull of gravity on the two objects

When the earth was formed and cooled, why did nickel and iron end up in the center of the earth while basalt and granite ended up in the outer layers

Astudent carefully transfers 30 g of water and 30 g of alcohol in a glass tube, forming two layers and filling the tube completely. after sealing the tube, the student mixes the solutions, and notices a bubble that forms in the tube. what is the mass of the contents in the glass tube after mixing?

The variability in marine salinity between habitats does not impact the fish living there. select the best answer from the choices provided t f