Which best describes eras and periods?
Eras have a smaller time span than periods.
Eras and periods are independent of each other.
Eras and periods both appear at the start of the Cambrian period.
Eras were more recently established on the time scale than periods.
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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?

Will a solution form when the solvent and solute are both nonpolar? a. not likely b. never c. most likely

Which of the following describes qualitative data? a) recording the temperature of a solid as it is warmed. b) noting the color of a solution as it is heated. c) measuring the volume of an object by water displacement. d) taking the mass of an object using a balance.