Which radioisotope is used to date fossils? a. oxygen-16 b. carbon-14 c. uranium-238 d. carbon-12

The tilt of the earth's axis of rotation is responsible for the a) ocean's tides. b) size of the moon. c) brightness of stars. d) earth’s seasons.

The chemical formula for emerald is be3al2(sio3)6.an emerald can be decided as

What is the typical rotational frequency frot for a molecule like n2 at room temperature (25∘c)? assume that d for this molecule is 1å=10−10m. take the total mass of an n2 molecule to be mn2=4.65×10−26kg. you will need to account for rotations around two axes (not just one) to find the correct frequency. express frot numerically in hertz, to three significant figures.