I would say B, because as you can see from the explanation of what a luster is described is. B matches the classifications
<span>Of SiF4 and SiBr4, the atom SiF4 is more polar. This is because the cation of both molecules are Silicon, but the anions of each are different. In SiF4, the anion is Fluorine, which is more electronegative than the Bromine in SiBr4, which creates a larger dipole, which results in a more polar molecule.</span>
Heart rate is controlled by the two branches of the autonomic (involuntary) nervous system. The sympathetic nervous system (SNS) and the parasympathetic nervous system (PNS). The sympathetic nervous system (SNS) releases the hormones (catecholamines - epinephrine and norepinephrine) to accelerate the heart rate. The parasympathetic nervous system (PNS) releases the hormone acetylcholine to slow the heart rate. Such factors as stress, caffeine, and excitement may temporarily accelerate your heart rate, while meditating or taking slow, deep breaths may help to slow your heart rate.
If the Earth were a disk with its surface perpendicular to the rays of sunlight, each point on it would receive the same amount of radiation. <span> However, the Earth is a sphere and aside from the part closest to the sun, where the rays of sunlight are perpendicular to the ground, its surface tilts with respect to the incoming rays of energy with the regions furthest away. Hope this answers the question.</span>