In the mid-section formula

• The mean depth is the average of depths of two consecutive sections
• The area of mid-sections is calculated by using mean depth
• The volume of the earth work is calculated by multiplying the mid-section area by the distance between the two sections
• The volume of the earth work is calculated by multiplying the mid-section area by the distance between the two original sections
• (a), (b) and (c) of the above.