What do these layers and their fossils suggest about Earth's history? ОА.
Lifeforms on Earth have been the same over time.
ОВ.
No lifeforms were present when these layers formed.
OC. Only one kind of lifeform lived where these layers formed.
OD
There have been changes in Earth's lifeforms over time.

The number of neutrons is equal to the atomic number minus the atomic mass. a. true b. false

Select all that apply. using a value of ksp = 1.8 x 10-2 for the reaction pbcl2 (s) pb+2(aq) + 2cl -(aq). the concentration of the products yield a ksp of 2.1 x 10-2:

The ozone molecule o3 has a permanent dipole moment of 1.8×10−30 cm. although the molecule is very slightly bent-which is why it has a dipole moment-it can be modeled as a uniform rod of length 2.5×10−10 m with the dipole moment perpendicular to the axis of the rod. suppose an ozone molecule is in a 8000 n/c uniform electric field. in equilibrium, the dipole moment is aligned with the electric field. but if the molecule is rotated by a small angle and released, it will oscillate back and forth in simple harmonic motion.what is the frequency f of oscillation?