How does radiometric dating scientists pinpoint the age of a fossil?
a. in radiometric dating, scientists mix the carbon in a fossil with carbon from similar fossils whose age they know. by comparing the carbon, they can tell the exact age of the fossil.
b. radiometric dating allows scientists to find fossils in only the lowest and oldest layers of sediment.
c. in radiometric dating, scientists place samples of a fossil in certain liquids until the samples dissolve. the rate at which they dissolve indicates the age of the fossil.

After getting the slide and microscope ready, stella is eager to see the microscopic pond water specimen! she crouches around her microscope and aligns her eye with the microscope’s eyepiece. but she's only able to see a bright white light. at this point, no specimens or cells are visible on stella's pond water slide. after taking a moment to collect her thoughts, stella realizes she can't see any lifeforms because .

Zoe decided to measure the hand length of each of her classmates. first she marked a line across each student's wrist and lined up a ruler from this mark to the top of the middle finger to measure the length. then she recorded the measurements in the table below. marla did this the same way for each classmate, and then zoe used this ruler to measure each straight line and record the data below. this data is invalid. what is the most likely reason why it is invalid? the ruler is marked in centimeters, but zoe recorded data in inches. the range of lengths is too wide, so zoe must have misread the ruler. marla’s complicated measuring procedure was overly confusing. marla could have been inconsistent while drawing outlines of fingers.

Which heredity condition causes a buildup of mucus in lungs and pancreas? a. cystic fibrosis b. heart disease c. huntington's disease d. sickle cell anemia