Whos down to tal im sooo bored lol

Which real-world scenarios below represent physical and chemical changes? -running a car -exploding fireworks -mixing water and powdered drink mix -combining oil and vinegar to make salad dressing -taking aspirin for a headache -diluting bleach with water-digesting dinner-spreading peanut butter on bread

Which of these expressions are correct variations of the combined gas law? p1v1t2 = p2v2t1 both

Why is the bottom layer of a trophic pyrimid the