Which major type of air mass typically brings cool, dry weather? maritime polar continental polar maritime tropical continental tropical

The correct answer is continental polar.  

When a huge air body sustains over a region for many weeks or days, the air body may modify its moisture and thermal characteristics on the basis of the water and land underneath it. The air interchanges heat with the water or land, either cooling or warming, unless and until its temperature nearly matches with that of the surface underneath it.  

The air body also loses or gains moisture on the basis of the moisture and temperature content of the surface. The air body that resembles the features of the surface under it is known as an air mass.  

The continental polar masses refers to the cold and dry, but not as cold as Arctic air masses. This generally produces farther to the south and usually dominate the weather scenario across the United States at the time of winter. The continental polar masses also produces at the time of summer, but generally, affect only the northern part of USA. These air masses are also accountable for bringing pleasant and clear weather at the time of summer to the north.  

The option B is the correct answer which is continental polar.

the answer that best describes the relative refractory period in the neuron is the resting membrane potential is restored, but concentrations of sodium and potassium are not restored to their original state.

the refractory period is the time during which another stimulus given to the neuron will not lead to a second potential. thus, because na+ channels are inactivated during this time, additional depolarizing stimuli do not lead to new action potentials.  

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the generally accepted parts of modern cell theory include: all known living things are made up of one or more cells. all living cells arise from pre-existing cells by division. the cell is the fundamental unit of structure and function in all living organisms.