A man sits on the grass eating a doughnut and sipping iced tea. The sun is a glowing ball in the sky, making the air warm. He gets up and makes sure his chainsaw is filled with gasoline. The fumes make him cough. He starts the motor, lifts his chainsaw, and saws a branch off a tree. The branch falls to the ground, knocking over his iced tea. By this time, the ice in his tea has completely melted. The tea pours over some ants that were munching on doughnut crumbs. With renewed energy from the snack, the ants grab their crumbs, lift them onto their backs, and scurry away. a. List the four states, or phases of matter and give one example of each from the story above.

In a laboratory experiment, a fermenting aqueous solution of glucose and yeast produces carbon dioxide gas and ethanol. the solution was heated by burning natural gas in a bunsen burner to distill the ethanol that formed in the flask. during the distillation, the ethanol evaporated and then condensed in the receiving flask. the flame of the burner was kept too close to the bottom of the flask and some of the glucose decomposed into a black carbon deposit on the inside of the flask. during this experiment the following changes occurred. which of these changes involved a physical change and not a chemical change? check all that apply. 1-condensation of ethanol 2-evaporation of ethanol 3- formation of carbon dioxide gas from glucose burning of natural gas 4-formation of ethanol from glucose by yeast 5-formation of a carbon deposit inside the flask

What is the empirical formula for c4h8o2

Answer asap : ( a. how does mucus prevent the entry of pathogens? b. describe two ways white blood cells protect us from pathogens.