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If you obtained a sample of Martian rock,determined the abundances of 238U and 207Pb in it,and found that for every 1 uranium atom there were 7 lead atoms,then what would the age of this rock be? Note that 238U decays to 207Pb with a half-life of 700 million years.Assume that there was no 207Pb in the rock when it originally formed.
Elasticity
The ability of an object or material to resume its normal shape after being stretched or compressed, often referring to skin or other tissues in the human body.
Stroke
A medical condition that occurs when the blood supply to part of the brain is interrupted or reduced, causing brain cells to die.
Hypertension
A condition characterized by consistently elevated blood pressure levels above normal ranges.
Disability
A physical or mental condition that limits a person's movements, senses, or activities.
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