Which of the following would be deposited by a river first
a: sand
b: silt
c: small rocks
d: large rocks

What is thought to have caused the mass extinction at the end of the cretaceous period?

Collin would like to use the data a coworker has entered in a database. the problem is the coworker's database software is different from collin's. collin should

Which rate indicates the number of children that would be born per women if she were to live to the end of her child-bearing years