is the pre- stressed force applied to tendon of a rectangular pre-stressed beam whose area of cross section is and sectional modulus is . The minimum stress on the beam subjected to a maximum bending moment is________________?
A. f = (P/A) – (Z/M)
B. f = (A/P) – (M/Z)
C. f = (P/A) – (M/Z)
D. f = (P/A) – (M/6Z)