Answer:
Researchers also found that the longer a male's tail feathers, the faster he was able to shake them. This effort would require more muscular strength, and might be a powerful signal of fitness to the females.
Explanation:
Answer:water
Explanation:because water is made ho2
Answer:
Knowledge gain through observation and experimentation.
Explanation:
Science is the systematic study of the structure and behaviour of the physical and natural world through observation and experiment. That knowledge which can be gain through observation and experimentations is considered as scientific knowledge and those knowledge which can be attain through other sources not observation and experiments is known as non-scientific knowledge so we can say that observation and experiments provide scientific knowledge.