Which pair of elements can be used to determine the age of a fossil that is over one billion years old?
lead, which is radioactive, and uranium, which is stable
carbon, which is radioactive, and nitrogen, which is stable
argon, which is radioactive, and lead, which is stable
potassium, which is radioactive, and argon, which is stable

The energy available as a result of the motion of a body is called energy. -potential -gravitational -kinetic -chemical

Aheterozygous normal male marries a woman with a sickle cell anemia. give the genotypes and possible phenotypes of the offspring

Scientists are conducting a study on the effectiveness of a new drug on memory loss. they are giving some of the test subjects the new drug to find out if it improves their long-term memory. which are possible limitations of this study? check all that apply. a) test subjects may want to participate in additional experiments. b) test subjects may think they should be paid more. c) test subjects may get bored and want to quit early. d) test subjects may have to travel during the experiment. e) test subjects may have full-time jobs. this is multiple choice. you for the !