What types of scientific field quantities are there

Based on the law of conservation of energy, which statement is false? answer- energy is lost when machines dont work right

What are the percent by mass of copper in penny lab

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?