x

Step

$y_1$

$y_2$

$y_3$

$y_4$

Enright [3]

1000

$4.1\times {10}^{-7}$

-

-

-

Ehigie [5]

1000

$4.2\times {10}^{-16}$

$2.1\times {10}^{-10}$

0

0

Four-Step

1000

0

0

0

0

Five-Step

1000

0

0

0

0