They would know if they see anything like traces of water or anything else that would be nessecary for a living organism to have. They look for these with technology like the hubble telescope as well as the drone on Mars to gather as much information as possible.
Answer:
Xylem cells have no cytoplasm or end walls, meaning they form a tube through which water can pass freely to allow water transport. Lignin strengthens the cell walls, helping to support the plant.
Ok so theirs this thing called asking your teacher for help especially when it’s such an easy question
it is the answer of buffalo behaviour
A hypothesis that has been verified by many scientists is called a scientific theory. Scientific theory can be derived from careful examination of facts and thorough testing and proving of the different scientists. A hypothesis is an intelligent guess about a certain situation or problem. Whenever this hypothesis would be verified many times by many scientists, this would be<span> under now the category of scientific theory.</span>