### Question:
Negation extends ERE { @Override public ERE copy() { return new Negation(children.get(0).copy()); } private  Negation(ERE child); static ERE get(ERE child); @Override EREType getEREType(); @Override String toString(); @Override ERE copy(); @Override boolean containsEpsilon(); @Override ERE derive(Symbol s);  }### Answer:
@Test public void testCopy() { ERE negation = Negation.get(empty); ERE copy = negation.copy(); assertEquals(negation, copy); }