Any help would be appreciated :))

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

Joan writes four numbers on the board in standard form, and then she writes their scientific notation

A2.5% (by mass) solution concentration signifies that there is a 2.5 % (by mass) solution concentration signifies that there is blank of solute in every 100 g of solution. of solute in every 100 g of solution