What can be a counterexample for "the reciprocal of each natural number is an integer"?

He amount of carbon-14 present in animal bones t years after the animal's death is given by p(t)equals=upper p 0 e superscript negative 0.00012097 tp0e−0.00012097t. how old is an ivory tusk that has lost 26% of its carbon-14?

Acoin bank containing only dimes and quarters has 12 more dimes than quarters. the total value of the coins is $11. how many quarters and dimes are in the coin bank?

Barbara deposited $300 in the bank. if the bank pays her simple interest at the rate of 4 percent per year, how much money will she have in her account at the end of 9 months?