### Question:
NormalRandomNumberGenerator implements RandomNumberGenerator { @Override public double[] getVector(int size) { ArgChecker.notNegative(size, "size"); double[] result = new double[size]; for (int i = 0; i < size; i++) { result[i] = normal.nextRandom(); } return result; } NormalRandomNumberGenerator(double mean, double sigma);  NormalRandomNumberGenerator(double mean, double sigma, RandomEngine engine); @Override double[] getVector(int size); @Override List<double[]> getVectors(int arraySize, int listSize);  }### Answer:
@Test public void test_array() { double[] result = GENERATOR.getVector(10); assertThat(result.length).isEqualTo(10); }