Answer: My best guess would be B but i might be wrong that sounds most right to me. :)
Explanation:
Answer:
In uranium-lead dating, for instance, the radioactive decay of uranium into lead proceeds at a reliable rate. Based on the very old zircon rock from Australia we know that the Earth is at least 4.374 billion years old.
And that's how after rounding we know that earth is 4.5 years old.
For most genes on the human X chromosome, 100% of XY males with mutant allele on the X chromosome will express the mutant phenotype.
50 % of human sperm cells that carry an X chromosome. There is 50 % chances that daughter of any male will not carry the gene and can't pass it on and 50 % chance that sons do not have the gene and it will be healthy. 50% chance that son have inherited the gene and express the trait or disorder.
If a Egg is fertilizes by sperm with X chromosome then zygote will be a female ' XX'. If the Egg is fertilizes by sperm with Y chromosome , then zygote will be male 'XY'.
To learn more about human sperm cells here
brainly.com/question/276208
#SPJ4
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.
