Lavoisier would have taken mercury and heated it up to 350 degrees centigrade in air and then found that a new compound was formed a red or yellow mineral which would be mercury oxide so the experimental observation would be the change in color of the mercury and the formation of a mineral with different properties from pure mercury.
All Living Organisms on earth. Plants, Humans, Animals.
Hey there! Here is your answer: Horseshoe crab is considered living fossils because they have existed unchanged for about 445 million years. They are usually not crab; they are not closely related to lobsters or crab. ... Horseshoe crab looks is almost the same with their ancient relatives despite the fact that they have been around for so long. I hope this helped! Your fellow Brainly user, GalaxyGamingKitty. (THE FOLLOWING INFORMATION HAS BEEN USED FROM GOOGLE)
I'd say C. an allergic reaction. Mainly because lots of people are allergic to many things and many people intend to have seasonal allergies cause by plants. Hope it helps!