Answer:
See attached picture.
Explanation:
Hello.
In this case, since butane has two common occurring structures, n-butane and isobutane, there is a way in which the tert-butyl radical can be formed upon the removal of a hydrogen from the isobutane form of butane as shown on the attached picture, wherein you can see that the radical is named by "tert" since the central carbon is bonded to three carbon atoms, that is why we classify it as tertiary. Moreover, it is a radical due to the presence of the bolded dot next to the tertiary carbon suggesting that it is very likely to bond with an other atom.
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