Acertain element has a half life of 4.5 billion years. (a). you find a rock containing a mixture of the element and lead. you determine that 35% of the original element remains; the other 65% decayed into lead. how old is the rock? (b). analysis of another rock shows that it contains 55% of it's original element; the other 45% decayed into lead. how old is the rock.

Step-by-step explanation:

Given that a  certain element has a half life of 4.5 billion years.

For half life of 4.5 billion years we have the equation as

= where t is in billions of years.

When P(t) = 35% of original we have

After 6.816 billion years.

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b) Here

After 3.88 billion years.

the sum of the lengths of any two sides of a triangle is greater than the length of the third side. if you take the three sides of a triangle and add them in pairs, the sum is greater than (not equal to) the third side. if that is not true, then it is not possible to construct a triangle with the given side lengths.

step-by-step explanation:

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