Cents. Refers to the position between the brackets in the middle part of the center sill.
In addition, it can be seen from the reinforcement that the upper side of the section at B0TH. There is a large proportion of steel bars, and the upper side is in tension. The reinforcement ratio of the lower side of the middle section is high and the lower side is in tension. If the bending moment diagram of the structure is correct, there will be no problem.