### Question:
LognormalSkewnessFromVolatilityCalculator implements DoubleBinaryOperator { @Override public double applyAsDouble(double sigma, double t) { double y = Math.sqrt(Math.exp(sigma * sigma * t) - 1); return y * (3 + y * y); }  @Override double applyAsDouble(double sigma, double t);  }### Answer:
@Test public void test() { assertThat(F.applyAsDouble(SIGMA, T)).isCloseTo(0.4560, offset(1e-4)); }