Middle question , what is the answer ?

In any energy conversion, some of the energy is lost to the environment as question 5 options: electrical energy potential energy sound energy thermal energy

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?

Chen drew a diagram to compare the ways in which different organisms obtain nitrogen. which label belongs to the area marked z?