Which of these formulas gives the exact equation for the UCL of s chart with a std. value for given?

Which of these formulas gives the exact equation for the UCL of s char

1.	Which of these formulas gives the exact equation for the UCL of s chart with a std. value for given?
A.	B<sub>6</sub>
B.	B<sub>5</sub>
C.	c<sub>4</sub>
D.	c<sub>3</sub>
Answer» B. B<sub>5</sub>