How would you use red, blue, and yellow marbles to model a carbon atom

The correct answer is - arrange yellow and blue in the center as proton and neutron while red as electrons revolving in a different shell.

Explanation:

The carbon atom has 6 protons and 6 neutrons present in the nucleus of the atom while 6 electrons present in the shell. The inner shell has two and the outer most shell has 4 electrons.

One can represent all three color balls as an electron, proton, and neutron to model the carbon atom.

i'd think it's paralell

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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