This is my outfit is it cute

Avariable that is not being directly tested during an experiment should be changed varied experimented controlled

What produces wave a)sound b) heats c)transfer of energy d)vibrations

How can you write e method for the experiment of separating sand from water by filtration process? 1-materials 2-steps 3-conclusion also the same for the separating process of water and salt by filtration or distillation. quick because i need to finish my hw