There are two lone pairs in the structure of nicotine. in general, localized lone pairs are much more reactive than delocalized lone pairs. with this information in mind, do you expect both lone pairs in nicotine to be reactive?

On the basis of the structure of nicotine, both the lone pair of electrons are localized and do not take part in delocalization. Thus, both the lone pairs are reactive.  

A localized lone pair remains near to one atom. A localized bond pair travels amid the two atoms. Resonance hybrids essentially comprise unusual electrons. These electrons step external to the boundaries being set up according to the Lewis theory, and thus are considered as delocalized.  

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.  

read more on -

the principles and empirical processes of discovery and demonstration considered characteristic of or necessary for scientific investigation, generally involving the observation of phenomena, the formulation of a hypothesis concerning the phenomena, experimentation to test the hypothesis, and development of a conclusion that confirms, rejects, or modifies the hypothesis.