Observe from the table for A4 given in Table 5.1 on page
Chapter 9, Problem 44E(choose chapter or problem)
Observe from the table for A4 given in Table 5.1 on page 111 that the subgroup given in Example 9 of this chapter is the only subgroup of A4 of order 4. Why does this imply that this subgroup must be normal in A4? Generalize this to arbitrary finite groups.
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