I think the correct answer would be the first option. As the hiker reaches the top of the mountain, the plastic bag would, most likely, expand. Before starting, the plastic bag would have a certain amount of gas particles inside. As the you hike, the pressure would decrease causing for the gas molecules to reestablish equilibrium thus pushing the bag outwards. In other words, expanding the bag. Also, base from the ideal gas equation, PV = nRT, at constant temperature and number of moles, pressure and volume are inversely related. Thus, as the pressure decreases, the volume of the system would increase accordingly.
This problem is providing us with the mass of propane, its enthalpy of combustion, and the initial and final temperature of water that can be heated from the burning of this fuel. At the end, the result turns out to be 42.27 L.
<h3>Combustion:</h3>
In chemistry, combustion reactions are based on the burning of fuels by using oxygen and producing both carbon dioxide and water. For propane, we will have:

Hence, we can calculate the heat released from this reaction by using the mass, which has to be converted to moles, and the given enthalpy of combustion:

<h3>Calorimetry:</h3>
In chemistry, we can analyze the mass-specific heat-temperature-heat relationship via the most general heat equation:

Thus, since Q was obtained from the previous problem, but the sign change because the released heat is now absorbed by the water, one can calculate the mass of water that rises from 20.0°C to 100.0°C with this heat:

Finally, we convert it to liters as required:

Learn more about calorimetry: brainly.com/question/1407669
Answer: Extracellular [Ca2+]
Explanation:
The sensitivity and density of the alpha receptors serve to <em>enhance the response to the release of</em> <em>norepinephrine (NE)</em> . However, they do not exert a strong influence as the concentration of calcium ions on the amount of <em>norepinephrine (NE)</em> released by sympathic nerve terminals.
The release of neurotransmitters depends more on either an external or internal stimulus.This results in an action potential which on reaching a nerve terminal, results in the opening of Ca²⁺ channels in the neuronal membrane. Because the extracellular concentration of Ca²⁺ is greater than the intracellular Ca²⁺ concentration, Ca²⁺ flows into the nerve terminal. This triggers a series of events that cause the vesicles containing <em>norepinephrine (NE)</em> to fuse with the plasma membrane and release <em>norepinephrine (NE)</em> into the synapse. The higher the action potential, the higher the Ca²⁺ flow into the terminals resulting in higher amount of <em>norepinephrine (NE)</em> into the synapse, and vice versa.
Catechol-O-methyltransferase (COMT) is one of several enzymes that degrade catecholamines such as dopamine, epinephrine, and norepinephrine. It serves a regulatory purpose to lower the concentration of norepinephrine upon its release from nerve terminals.
Sediments move one place to another in the process called “ erosion”
Answer:
75.12 J
Explanation:
Applying,
Q = CΔT................ equation 1
Where Q = amount of heat, C = Heat capacity, ΔT = temperature rise.
From the question,
Given: C = 62.6 J/K, ΔT = 1.20°C
Substitute these values into equation 1
Q = 62.6(1.20)
Q = 75.12 J
Hence the amount of heat it absorbed is 75.12 J