In an unweathered sample of detrital sedimentary rock, the ratio of an unstable isotope to its stable daughter isotope is 1/15. If no daughters were present at the time the rock cooled below closure temperature, and the half-life of the reaction is 50 million years, how old is the rock?

a. 200 million years
b. 400 million years
c. 750 million years
d. None of the above are correct

Compare demographic and environmental effects of the columbian

Which of the following is an example of a policy that may be implemented by a business that has trouble with employees using the internet for their own personal needs? a. all employees will have to take a safety training class. b. employees caught using the internet for personal needs will have to take a professional development class. c. personal interviews will be conducted to find out who is using the internet for personal needs. d. employees will be monitored, but nothing will happen if their employer catches them using the internet for personal needs.

Why do u think kenny is afraid when he realizes that the reading he has chosen to do will be for byrons calss? what happens after the reading that surprises kenny?