What is pressure head (h_w) and total head (h) at point A, if h = 50 feet?
A. h_w = 0 feet, h = 50 feet
B. h_w = 50 feet, h = 0 feet
C. h_w = 25 feet, h = 25 feet
D. h_w = 20 feet, h = 30 feet