In the following pair, determine whether the two represent resonance contributors of a single species or depict different substances. If two structures are not resonance contributors, explain why? a. N¨−N≡N: and N¨=N=N:N¨=N=N: 
b. N¨−N≡N:N¨−N≡N: and N¨−N=N¨N¨−N=N ¨ 
c. N¨−N≡N:N¨−N≡N: and N¨−N¨−N¨N¨−N¨ −N¨

Particles vibrate in a rigid structure and do not move relative to their neighbors.

Which are forms of frozen water? check all that apply. dew frost hail rain sleet

Consider a culture medium on which only gram-positive organisms such as staphylococcus aureus colonies can grow due to an elevated nacl level. a yellow halo surrounds the growth, indicating the bacterium fermented a sugar in the medium, decreasing the ph as a result and changing the color of a ph indicator chemical. this type of medium would be referred to as a differential and enrichment culture.