Urgently!
crickets perceive sounds with a frequency of 300 - 8000 hz. what is the period of sound vibrations and the length of the sound wave perceived by an insect?

Which energy transformation occurs in the core of a nuclear reactor? nuclear energy mechanical energy nuclear energy - thermal energy thermal energy -- nuclear energy mechanical energy - nuclear energy

These models show the electron structures of two different nonmetal elements. which element is likely more reactive, and why? element 1 is more reactive because it has fewer electron shells and is toward the top of its group on the periodic table. element 1 is more reactive because it has more electrons in its valence shell and is farther to the right on the periodic table. element 2 is more reactive because it does not have a valence shell close to the nucleus, so it will attract electrons. element 2 is more reactive because it does not have a full valence shell, so it will attract electrons.

Imagine you are standing in the antarctic during the southern hemisphere summer. the sky is clear and blue. there are no clouds in the sky. your shadow is cast on the icy ground. what is the color of the shadow?