Willian’s line follows the law (where b = A constant representing the shape of the Willian’s line, a = Another constant i.e. no load consumption per hour, I.P. = Indicated power, and m = Steam consumption per hour)

• A. .P. = a × m + b
• B. = a + b × I.P.
• C. .P. = b × m + a
• D. = (b/I.P.) - a