What characteristic do tantalum and tin have in common?
1.used infrequently in modern manufacturing
2.beneficial for human health
3.mined in the united states and canada
4.categorized as conflict minerals

4. categorized as conflict minerals

Explanation:

Conflict materals are mined in conflict places and the funds that a derived from trading the mineral is used to fund wars or fighting.

Option 4, categorized as conflict minerals

Explanation:

The four minerals primarily  

a)Coltan – Titanium is extracted from this

b)Cassiterite -  tin is extracted from this

c)Gold  

d)Wolframite – tungsten is derived from this

And their derivatives are considered as conflict minerals. These are collectively known as T3G minerals.  

A regulation has been defined to report conflict minerals compliance in which the information about the entire supply chain along with essential information such as country from which the mineral originated, smelters and refineries being utilizes etc. to cater the conflict between the Congo Republic and its adjoining countries.  

Hence, option 4 is correct

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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