Rank the following radicals in decreasing order of stability. Classify each as primary, secondary, or tertiary.
a. The isopentyl radical, (CH3)2 CHCH2—⋅CH2
b. The 3-methyl-2-butyl radical, CH3—⋅CH—CH(CH3)2
c. The 2-methyl-2-butyl radical, CH3—⋅C(CH3)CH2CH3
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