If1/4 of the parent isotope remains, and 3/4 has been changed to the daughter isotope, how many half-lives have occurred?

Awater molecule is polar because there is an uneven distribution of these between the oxygen and hydrogen atoms.

During an experiment, readings for blood pressure in a persons body were found to be constant . however , when he measured by a different blood pressure cuff , the readings differed by 15 points for each reading. this difference indicates that the results are

As molecules are formed from metabolism, entropy __ and the universe becomes less disordered. a. is decreased b. is increased c. moves closer to equilibrium d. is unchanged