I believe the answer is: Nitric oxide
<span>Nitric oxide could be synthesized on demand, because it is considered to be membrane permeant that cannot be stored. Calcium influx through </span><span>The N-methyl-D-aspartate </span>receptor activates nitric oxide synthase (NOS), which synthesizes Nitric oxide from L-arginine which allow it <span> to act as a retrograde messenger from the dendrite to the terminal button. </span>
<h2>The Answer Is:</h2><h3><u>B</u><u>:</u><u>Congress could not decide whether to allow slavery in the territories</u></h3>
Testing the DNA and RNA of the butterflies and putting them into the computerized system with the name of the specific butterfly along with the sample DNA and RNA of the butterflies can correctly identify each of the species of butterflies and solve that problem.
The US borders Mexico, so if Mexico became a part of the axis powers the US would have to fear an attack on its mainland (from either Mexican forces or other axis forces stationed in Mexico), whereas if Mexico remained neutral the US mainland would be safe.
