The cross-section of a cannel is a trapezium in shape. If the cannel is 20 m wide at the top and 12 m wide at the bottom and the area of cross-section is 800 sq m, the depth of cannel is?  Choose the correct choice from the following answers
A) 76  B) 50  C) 27  D) 80  E) 25
1/2 * d (20 + 12) = 800   d = 50   Answer: 50
<result>B</result>
The cross-section of a cannel is a trapezium in shape. If the cannel is 20 m wide at the top and 12 m wide at the bottom and the area of cross-section is 800 sq m, the depth of cannel is?