if the ratio of velocity of light in air to the velocity in another medium is 0.25.what is the refractive index?

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

Can someone check my work 98 5.05 acids and bases for this assignment you will be comparing acids and bases. the chart below will you organize the information needed: acids bases chemical properties (2) deodorant detergent vinger dish soap physical properties (2) orange juice toilet cleaner drain cleaner window cleaner ph level acid ph goes from 0-4 bases ph goes from 10-14 examples around you (2) vinger coffee lemon juice dark chocolate

Which of these are physical changes in matter? check all that apply boiling water a pencil being sharpened exploding dynamite freezing water rotting cheese