How did geologists decide where one division of the geologic time scale ends and the next begins?

the law of superpostion

events in the history of life on earth, like mass extinctions

they divided the time equally between eras

the placement of fossils throughout the surface layers of earth

Awoman whose sister tested positive for a specific mutation in the brca1 gene, which increases the risk for breast and ovarian cancer, is found not to have that mutation but does have a mutation of unknown significance near the known mutation site. how should this woman be counseled? select one: a. she should be informed that her risk for breast cancer is greater than the general population but not as great as her sister’s risk. b. she should be informed that because she does not have the mutation, her risk for breast cancer is not greater than that of the general population. c. she should be informed of her gene mutation status and be presented with all the available prophylaxis options and reconstruction options. d. she should be informed that she does not have the specific mutation but that because another mutation is present she should be vigilant about screening

What process occurs during cellular development as the cell changes into a specific type of cell with specialized functions? a. binary fission b. fusion c. differentiation d. meiosis

The graph shows how much money the south dakota livestock industry earns annually. according to the graph, which industry would experience the greatest financial impact from a loss of pastureland